diff --git a/src/AudacityApp.cpp b/src/AudacityApp.cpp
index c22835090..3c6272465 100644
--- a/src/AudacityApp.cpp
+++ b/src/AudacityApp.cpp
@@ -810,9 +810,8 @@ void AudacityApp::MacNewFile()
    // This method should only be used on the Mac platform
    // when no project windows are open.
 
-   if (AllProjects{}.empty()) {
-      CreateNewAudacityProject();
-   }
+   if (AllProjects{}.empty())
+      (void) ProjectManager::New();
 }
 
 #endif //__WXMAC__
@@ -880,7 +879,7 @@ bool AudacityApp::MRUOpen(const FilePath &fullPathStr) {
          // Test here even though AudacityProject::OpenFile() also now checks, because
          // that method does not return the bad result.
          // That itself may be a FIXME.
-         if (AudacityProject::IsAlreadyOpen(fullPathStr))
+         if (ProjectManager::IsAlreadyOpen(fullPathStr))
             return false;
 
          // DMM: If the project is dirty, that means it's been touched at
@@ -893,12 +892,15 @@ bool AudacityApp::MRUOpen(const FilePath &fullPathStr) {
          // there are no tracks, but there's an Undo history, etc, then
          // bad things can happen, including data files moving to the NEW
          // project directory, etc.
-         if (proj && (proj->GetDirty() || !TrackList::Get( *proj ).empty()))
+         if (proj && (
+            ProjectManager::Get( *proj ).GetDirty() ||
+            !TrackList::Get( *proj ).empty()
+         ) )
             proj = nullptr;
          // This project is clean; it's never been touched.  Therefore
          // all relevant member variables are in their initial state,
          // and it's okay to open a NEW project inside this window.
-         AudacityProject::OpenProject( proj, fullPathStr );
+         ( void ) ProjectManager::OpenProject( proj, fullPathStr );
       }
       else {
          // File doesn't exist - remove file from history
@@ -936,7 +938,7 @@ void AudacityApp::OnMRUFile(wxCommandEvent& event) {
    // PRL: Don't call SafeMRUOpen
    // -- if open fails for some exceptional reason of resource exhaustion that
    // the user can correct, leave the file in history.
-   if (!AudacityProject::IsAlreadyOpen(fullPathStr) && !MRUOpen(fullPathStr))
+   if (!ProjectManager::IsAlreadyOpen(fullPathStr) && !MRUOpen(fullPathStr))
       history.RemoveFileFromHistory(n);
 }
 
@@ -1073,7 +1075,7 @@ bool AudacityApp::OnExceptionInMainLoop()
          // Restore the state of the project to what it was before the
          // failed operation
          if (pProject) {
-            pProject->RollbackState();
+            ProjectManager::Get( *pProject ).RollbackState();
 
             // Forget pending changes in the TrackList
             TrackList::Get( *pProject ).ClearPendingTracks();
@@ -1511,7 +1513,7 @@ bool AudacityApp::OnInit()
    // Root cause is problem with wxSplashScreen and other dialogs co-existing, that
    // seemed to arrive with wx3.
    {
-      project = CreateNewAudacityProject();
+      project = ProjectManager::New();
       mCmdHandler->SetProject(project);
       wxWindow * pWnd = MakeHijackPanel();
       if (pWnd)
@@ -2081,7 +2083,7 @@ void AudacityApp::OnMenuNew(wxCommandEvent & event)
    // all platforms.
 
    if(AllProjects{}.empty())
-      CreateNewAudacityProject();
+      (void) ProjectManager::New();
    else
       event.Skip();
 }
@@ -2097,7 +2099,7 @@ void AudacityApp::OnMenuOpen(wxCommandEvent & event)
 
 
    if(AllProjects{}.empty())
-      AudacityProject::OpenFiles(NULL);
+      ProjectManager::OpenFiles(NULL);
    else
       event.Skip();
 
diff --git a/src/AutoRecovery.cpp b/src/AutoRecovery.cpp
index 6fd32beee..129c69cb0 100644
--- a/src/AutoRecovery.cpp
+++ b/src/AutoRecovery.cpp
@@ -227,7 +227,7 @@ static bool RecoverAllProjects(AudacityProject** pproj)
       // Open project. When an auto-save file has been opened successfully,
       // the opened auto-save file is automatically deleted and a NEW one
       // is created.
-      AudacityProject::OpenProject( proj, files[i], false );
+      (void) ProjectManager::OpenProject( proj, files[i], false );
    }
 
    return true;
diff --git a/src/BatchCommands.cpp b/src/BatchCommands.cpp
index f6b7d342e..44549ffda 100644
--- a/src/BatchCommands.cpp
+++ b/src/BatchCommands.cpp
@@ -842,7 +842,7 @@ bool MacroCommands::ApplyMacro(
       if (!res) {
          if(proj) {
             // Macro failed or was cancelled; revert to the previous state
-            proj->RollbackState();
+            ProjectManager::Get( *proj ).RollbackState();
          }
       }
    } );
@@ -888,7 +888,7 @@ bool MacroCommands::ApplyMacro(
    if (!proj)
       return false;
    if( MacroReentryCount <= 1 )
-      proj->PushState(longDesc, shortDesc);
+      ProjectManager::Get( *proj ).PushState(longDesc, shortDesc);
    return true;
 }
 
diff --git a/src/BatchProcessDialog.cpp b/src/BatchProcessDialog.cpp
index a56b5712d..8fc7266a5 100644
--- a/src/BatchProcessDialog.cpp
+++ b/src/BatchProcessDialog.cpp
@@ -461,7 +461,7 @@ void ApplyMacroDialog::OnApplyToFiles(wxCommandEvent & WXUNUSED(event))
       fileList->EnsureVisible(i);
 
       auto success = GuardedCall< bool >( [&] {
-         project->Import(files[i]);
+         ProjectManager::Get( *project ).Import(files[i]);
          ProjectWindow::Get( *project ).ZoomAfterImport(nullptr);
          SelectActions::DoSelectAll(*project);
          if (!mMacroCommands.ApplyMacro(mCatalog))
@@ -476,7 +476,7 @@ void ApplyMacroDialog::OnApplyToFiles(wxCommandEvent & WXUNUSED(event))
       if (!success)
          break;
       
-      project->ResetProjectToEmpty();
+      ProjectManager::Get( *project ).ResetProjectToEmpty();
    }
 
    Show();
diff --git a/src/HistoryWindow.cpp b/src/HistoryWindow.cpp
index 1ba5eb27c..10557adc5 100644
--- a/src/HistoryWindow.cpp
+++ b/src/HistoryWindow.cpp
@@ -254,7 +254,7 @@ void HistoryWindow::OnDiscard(wxCommandEvent & WXUNUSED(event))
 
    mSelected -= i;
    mManager->RemoveStates(i);
-   mProject->SetStateTo(mSelected + 1);
+   ProjectManager::Get( *mProject ).SetStateTo(mSelected + 1);
 
    while(--i >= 0)
       mList->DeleteItem(i);
@@ -292,7 +292,7 @@ void HistoryWindow::OnItemSelected(wxListEvent &event)
    // entry.  Doing so can cause unnecessary delays upon initial load or while
    // clicking the same entry over and over.
    if (selected != mSelected) {
-      mProject->SetStateTo(selected + 1);
+      ProjectManager::Get( *mProject ).SetStateTo(selected + 1);
    }
    mSelected = selected;
 
diff --git a/src/LabelTrack.cpp b/src/LabelTrack.cpp
index 709afc905..6ce4344e6 100644
--- a/src/LabelTrack.cpp
+++ b/src/LabelTrack.cpp
@@ -1813,7 +1813,7 @@ unsigned LabelTrack::KeyDown(wxKeyEvent & event, ViewInfo &viewInfo, wxWindow *W
    // Pass keystroke to labeltrack's handler and add to history if any
    // updates were done
    if (OnKeyDown(viewInfo.selectedRegion, event)) {
-      pProj->PushState(_("Modified Label"),
+      ProjectManager::Get( *pProj ).PushState(_("Modified Label"),
          _("Label Edit"),
          UndoPush::CONSOLIDATE);
    }
@@ -1845,7 +1845,7 @@ unsigned LabelTrack::Char(wxKeyEvent & event, ViewInfo &viewInfo, wxWindow *)
    AudacityProject *const pProj = GetActiveProject();
 
    if (OnChar(viewInfo.selectedRegion, event))
-      pProj->PushState(_("Modified Label"),
+      ProjectManager::Get( *pProj ).PushState(_("Modified Label"),
       _("Label Edit"),
       UndoPush::CONSOLIDATE);
 
@@ -2130,13 +2130,13 @@ bool LabelTrack::OnChar(SelectedRegion &WXUNUSED(newSel), wxKeyEvent & event)
          }
          SetSelected(true);
          AddLabel(selectedRegion, title, -2);
-         p->PushState(_("Added label"), _("Label"));
+         ProjectManager::Get( *p ).PushState(_("Added label"), _("Label"));
          return false;
       }
       else {
          SetSelected(true);
          AddLabel(selectedRegion);
-         p->PushState(_("Added label"), _("Label"));
+         ProjectManager::Get( *p ).PushState(_("Added label"), _("Label"));
       }
    }
 
@@ -2230,7 +2230,7 @@ void LabelTrack::OnContextMenu(wxCommandEvent & evt)
    case OnCutSelectedTextID:
       if (CutSelectedText())
       {
-         p->PushState(_("Modified Label"),
+         ProjectManager::Get( *p ).PushState(_("Modified Label"),
                       _("Label Edit"),
                       UndoPush::CONSOLIDATE);
       }
@@ -2245,7 +2245,7 @@ void LabelTrack::OnContextMenu(wxCommandEvent & evt)
    case OnPasteSelectedTextID:
       if (PasteSelectedText(selectedRegion.t0(), selectedRegion.t1()))
       {
-         p->PushState(_("Modified Label"),
+         ProjectManager::Get( *p ).PushState(_("Modified Label"),
                       _("Label Edit"),
                       UndoPush::CONSOLIDATE);
       }
@@ -2257,7 +2257,7 @@ void LabelTrack::OnContextMenu(wxCommandEvent & evt)
       if (ndx != -1)
       {
          DeleteLabel(ndx);
-         p->PushState(_("Deleted Label"),
+         ProjectManager::Get( *p ).PushState(_("Deleted Label"),
                       _("Label Edit"),
                       UndoPush::CONSOLIDATE);
       }
@@ -3104,7 +3104,8 @@ void LabelTrack::DoEditLabels
 #endif
 
    if (dlg.ShowModal() == wxID_OK) {
-      project.PushState(_("Edited labels"), _("Label"));
+      ProjectManager::Get( project )
+         .PushState(_("Edited labels"), _("Label"));
       window.RedrawProject();
    }
 }
diff --git a/src/Menus.cpp b/src/Menus.cpp
index 36488d641..f38ff99eb 100644
--- a/src/Menus.cpp
+++ b/src/Menus.cpp
@@ -327,7 +327,8 @@ void MenuManager::ModifyUndoMenuItems(AudacityProject &project)
       commandManager.Modify(wxT("Undo"),
                              wxString::Format(_("&Undo %s"),
                                               desc));
-      commandManager.Enable(wxT("Undo"), project.UndoAvailable());
+      commandManager.Enable(wxT("Undo"),
+         ProjectManager::Get( project ).UndoAvailable());
    }
    else {
       commandManager.Modify(wxT("Undo"),
@@ -339,7 +340,8 @@ void MenuManager::ModifyUndoMenuItems(AudacityProject &project)
       commandManager.Modify(wxT("Redo"),
                              wxString::Format(_("&Redo %s"),
                                               desc));
-      commandManager.Enable(wxT("Redo"), project.RedoAvailable());
+      commandManager.Enable(wxT("Redo"),
+         ProjectManager::Get( project ).RedoAvailable());
    }
    else {
       commandManager.Modify(wxT("Redo"),
@@ -519,10 +521,11 @@ CommandFlag MenuManager::GetUpdateFlags
    if (!mLastEffect.empty())
       flags |= HasLastEffectFlag;
 
-   if (project.UndoAvailable())
+   auto &projectManager = ProjectManager::Get( project );
+   if (projectManager.UndoAvailable())
       flags |= UndoAvailableFlag;
 
-   if (project.RedoAvailable())
+   if (projectManager.RedoAvailable())
       flags |= RedoAvailableFlag;
 
    if (ViewInfo::Get( project ).ZoomInAvailable() && (flags & TracksExistFlag))
diff --git a/src/MixerBoard.cpp b/src/MixerBoard.cpp
index 2ebee5d23..95446943c 100644
--- a/src/MixerBoard.cpp
+++ b/src/MixerBoard.cpp
@@ -412,7 +412,8 @@ void MixerTrackCluster::HandleSliderGain(const bool bWantPushState /*= false*/)
    // Update the TrackPanel correspondingly.
    TrackPanel::Get( *mProject ).RefreshTrack(mTrack.get());
    if (bWantPushState)
-      mProject->PushState(_("Moved gain slider"), _("Gain"), UndoPush::CONSOLIDATE );
+      ProjectManager::Get( *mProject )
+         .PushState(_("Moved gain slider"), _("Gain"), UndoPush::CONSOLIDATE );
 }
 
 #ifdef EXPERIMENTAL_MIDI_OUT
@@ -425,7 +426,9 @@ void MixerTrackCluster::HandleSliderVelocity(const bool bWantPushState /*= false
    // Update the TrackPanel correspondingly.
    TrackPanel::Get( *mProject ).RefreshTrack(mTrack.get());
    if (bWantPushState)
-      mProject->PushState(_("Moved velocity slider"), _("Velocity"), UndoPush::CONSOLIDATE);
+      ProjectManager::Get( *mProject )
+         .PushState(_("Moved velocity slider"), _("Velocity"),
+            UndoPush::CONSOLIDATE);
 }
 #endif
 
@@ -441,7 +444,9 @@ void MixerTrackCluster::HandleSliderPan(const bool bWantPushState /*= false*/)
    TrackPanel::Get( *mProject ).RefreshTrack(mTrack.get());
 
    if (bWantPushState)
-      mProject->PushState(_("Moved pan slider"), _("Pan"), UndoPush::CONSOLIDATE );
+      ProjectManager::Get( *mProject )
+         .PushState(_("Moved pan slider"), _("Pan"),
+            UndoPush::CONSOLIDATE );
 }
 
 void MixerTrackCluster::ResetMeter(const bool bResetClipping)
diff --git a/src/Project.cpp b/src/Project.cpp
index 7d352c170..837e0cd26 100644
--- a/src/Project.cpp
+++ b/src/Project.cpp
@@ -105,7 +105,6 @@ scroll information.  It also has some status flags.
 #include "AudioIO.h"
 #include "Dependencies.h"
 #include "Diags.h"
-#include "export/Export.h"
 #include "InconsistencyException.h"
 #include "import/Import.h"
 #include "KeyboardCapture.h"
@@ -161,6 +160,8 @@ scroll information.  It also has some status flags.
 #include "commands/CommandType.h"
 
 #include "prefs/ThemePrefs.h"
+#include "export/Export.h"
+
 #include "prefs/QualityPrefs.h"
 #include "prefs/TracksPrefs.h"
 
@@ -604,7 +605,7 @@ public:
                FileActions::DoImportMIDI(mProject, name);
             else
 #endif
-               mProject->Import(name);
+               ProjectManager::Get( *mProject ).Import(name);
          }
 
          auto &window = ProjectWindow::Get( *mProject );
@@ -622,8 +623,9 @@ private:
 
 
 XMLTagHandler *
-AudacityProject::ImportHandlerFactory( AudacityProject &project ) {
-   auto &ptr = project.mImportXMLTagHandler;
+ProjectManager::ImportHandlerFactory( AudacityProject &project ) {
+   auto &projectManager = Get( project );
+   auto &ptr = projectManager.mImportXMLTagHandler;
    if (!ptr)
       ptr =
          std::make_unique<ImportXMLTagHandler>( &project );
@@ -631,7 +633,7 @@ AudacityProject::ImportHandlerFactory( AudacityProject &project ) {
 }
 
 ProjectFileIORegistry::Entry
-AudacityProject::sImportHandlerFactory{
+ProjectManager::sImportHandlerFactory{
    wxT("import"), ImportHandlerFactory
 };
 
@@ -659,7 +661,8 @@ bool ImportXMLTagHandler::HandleXMLTag(const wxChar *tag, const wxChar **attrs)
    // Guard this call so that C++ exceptions don't propagate through
    // the expat library
    GuardedCall(
-      [&] { mProject->Import(strAttr, &trackArray); },
+      [&] {
+         ProjectManager::Get( *mProject ).Import(strAttr, &trackArray); },
       [&] (AudacityException*) { trackArray.clear(); }
    );
 
@@ -695,7 +698,7 @@ bool ImportXMLTagHandler::HandleXMLTag(const wxChar *tag, const wxChar **attrs)
    return bSuccess;
 };
 
-AudacityProject *CreateNewAudacityProject()
+AudacityProject *ProjectManager::New()
 {
    wxRect wndRect;
    bool bMaximized = false;
@@ -715,8 +718,15 @@ AudacityProject *CreateNewAudacityProject()
    AllProjects{}.Add( sp );
    auto p = sp.get();
    auto &project = *p;
+   auto &projectManager = Get( project );
    auto &window = GetProjectFrame( *p );
 
+   MissingAliasFilesDialog::SetShouldShow(true);
+   MenuManager::Get( project ).CreateMenusAndCommands( project );
+
+   projectManager.InitialState();
+   projectManager.RestartTimer();
+
    // wxGTK3 seems to need to require creating the window using default position
    // and then manually positioning it.
    window.SetPosition(wndRect.GetPosition());
@@ -729,8 +739,23 @@ AudacityProject *CreateNewAudacityProject()
       // window.Iconize(TRUE);
    }
 
-   //Initialise the Listener
-   gAudioIO->SetListener(p);
+   //Initialise the Listeners
+   gAudioIO->SetListener( &projectManager );
+   SelectionBar::Get( project ).SetListener( &projectManager );
+#ifdef EXPERIMENTAL_SPECTRAL_EDITING
+   SpectralSelectionBar::Get( project ).SetListener( &projectManager );
+#endif
+
+   project.UpdatePrefs();
+
+#if wxUSE_DRAG_AND_DROP
+   // We can import now, so become a drag target
+//   SetDropTarget(safenew AudacityDropTarget(this));
+//   mTrackPanel->SetDropTarget(safenew AudacityDropTarget(this));
+
+   // SetDropTarget takes ownership
+   TrackPanel::Get( project ).SetDropTarget( safenew DropTarget( &project ) );
+#endif
 
    //Set the NEW project as active:
    SetActiveProject(p);
@@ -1034,8 +1059,9 @@ int AudacityProject::NextWindowID()
 // a bad compilation dependency.  The event was never emitted anywhere.  I
 // preserve it and its handler here but I move it to remove the dependency.
 // Asynchronous open
-DECLARE_EXPORTED_EVENT_TYPE(AUDACITY_DLL_API, EVT_OPEN_AUDIO_FILE, -1);
-DEFINE_EVENT_TYPE(EVT_OPEN_AUDIO_FILE);
+wxDECLARE_EXPORTED_EVENT(AUDACITY_DLL_API,
+                         EVT_OPEN_AUDIO_FILE, wxCommandEvent);
+wxDEFINE_EVENT(EVT_OPEN_AUDIO_FILE, wxCommandEvent);
 
 BEGIN_EVENT_TABLE(AudacityProject, wxFrame)
    EVT_MENU(wxID_ANY, AudacityProject::OnMenu)
@@ -1050,11 +1076,9 @@ BEGIN_EVENT_TABLE(AudacityProject, wxFrame)
    EVT_COMMAND_SCROLL_LINEDOWN(HSBarID, AudacityProject::OnScrollRightButton)
    EVT_COMMAND_SCROLL(HSBarID, AudacityProject::OnScroll)
    EVT_COMMAND_SCROLL(VSBarID, AudacityProject::OnScroll)
-   EVT_TIMER(AudacityProjectTimerID, AudacityProject::OnTimer)
    // Fires for menu with ID #1...first menu defined
    EVT_UPDATE_UI(1, AudacityProject::OnUpdateUI)
    EVT_ICONIZE(AudacityProject::OnIconize)
-   EVT_COMMAND(wxID_ANY, EVT_OPEN_AUDIO_FILE, AudacityProject::OnOpenAudioFile)
    EVT_COMMAND(wxID_ANY, EVT_TOOLBAR_UPDATED, AudacityProject::OnToolBarUpdate)
    //mchinen:multithreaded calls - may not be threadsafe with CommandEvent: may have to change.
 END_EVENT_TABLE()
@@ -1088,8 +1112,6 @@ AudacityProject::AudacityProject(wxWindow * parent, wxWindowID id,
    statusBar->SetName(wxT("status_line"));     // not localized
    mProjectNo = mProjectCounter++; // Bug 322
 
-   MissingAliasFilesDialog::SetShouldShow(true);
-
    mLastSavedTracks.reset();
 
    auto &viewInfo = ViewInfo::Get( *this );
@@ -1126,10 +1148,6 @@ AudacityProject::AudacityProject(wxWindow * parent, wxWindowID id,
    //
    // Create the ToolDock
    //
-   SelectionBar::Get( project ).SetListener( &project );
-#ifdef EXPERIMENTAL_SPECTRAL_EDITING
-   SpectralSelectionBar::Get( project ).SetListener( &project );
-#endif
    ToolManager::Get( project ).LayoutToolBars();
 
    //
@@ -1202,8 +1220,6 @@ AudacityProject::AudacityProject(wxWindow * parent, wxWindowID id,
  
    mPlaybackScroller = std::make_unique<PlaybackScroller>(this);
 
-   MenuManager::Get( project ).CreateMenusAndCommands( project );
-
    // LLL: When Audacity starts or becomes active after returning from
    //      another application, the first window that can accept focus
    //      will be given the focus even if we try to SetFocus().  By
@@ -1273,7 +1289,6 @@ AudacityProject::AudacityProject(wxWindow * parent, wxWindowID id,
    // MM: Give track panel the focus to ensure keyboard commands work
    trackPanel.SetFocus();
 
-   InitialState();
    FixScrollbars();
    ruler.SetLeftOffset(trackPanel.GetLeftOffset());  // bevel on AdornedRuler
 
@@ -1309,25 +1324,8 @@ AudacityProject::AudacityProject(wxWindow * parent, wxWindowID id,
    statusBar->SetStatusText(msg, mainStatusBarField);
    ControlToolBar::Get( project ).UpdateStatusBar(this);
 
-   mTimer = std::make_unique<wxTimer>(this, AudacityProjectTimerID);
-   RestartTimer();
-
-   UpdatePrefs();
-
-#if wxUSE_DRAG_AND_DROP
-   // We can import now, so become a drag target
-//   SetDropTarget(safenew AudacityDropTarget(this));
-//   mTrackPanel->SetDropTarget(safenew AudacityDropTarget(this));
-
-   // SetDropTarget takes ownership
-   trackPanel.SetDropTarget(safenew DropTarget(this));
-#endif
-
    wxTheApp->Bind(EVT_THEME_CHANGE, &AudacityProject::OnThemeChange, this);
 
-   project.Bind(EVT_PROJECT_STATUS_UPDATE,
-      &AudacityProject::OnStatusChange, this);
-
 #ifdef EXPERIMENTAL_DA2
    ClearBackground();// For wxGTK.
 #endif
@@ -1362,7 +1360,7 @@ DefaultPlayOptions( AudacityProject &project )
    options.captureMeter = projectAudioIO.GetCaptureMeter();
    options.playbackMeter = projectAudioIO.GetPlaybackMeter();
    options.timeTrack = TrackList::Get( project ).GetTimeTrack();
-   options.listener = &project;
+   options.listener = &ProjectManager::Get( project );
    return options;
 }
 
@@ -1379,7 +1377,7 @@ DefaultSpeedPlayOptions( AudacityProject &project )
    options.captureMeter = projectAudioIO.GetCaptureMeter();
    options.playbackMeter = projectAudioIO.GetPlaybackMeter();
    options.timeTrack = TrackList::Get( project ).GetTimeTrack();
-   options.listener = &project;
+   options.listener = &ProjectManager::Get( project );
    return options;
 }
 
@@ -1467,10 +1465,11 @@ void AudacityProject::SetProjectTitle( int number)
    SetName(name);       // to make the nvda screen reader read the correct title
 }
 
-bool AudacityProject::SnapSelection()
+bool ProjectManager::SnapSelection()
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &settings = ProjectSettings::Get( project );
+   auto &window = project;
    auto snapTo = settings.GetSnapTo();
    if (snapTo != SNAP_OFF) {
       auto &viewInfo = ViewInfo::Get( project );
@@ -1492,7 +1491,7 @@ bool AudacityProject::SnapSelection()
 
       if (t0 != oldt0 || t1 != oldt1) {
          selectedRegion.setTimes(t0, t1);
-         TP_DisplaySelection();
+         window.TP_DisplaySelection();
          return true;
       }
    }
@@ -1500,33 +1499,34 @@ bool AudacityProject::SnapSelection()
    return false;
 }
 
-double AudacityProject::AS_GetRate()
+double ProjectManager::AS_GetRate()
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &settings = ProjectSettings::Get( project );
    return settings.GetRate();
 }
 
 // Typically this came from the SelectionToolbar and does not need to 
 // be communicated back to it.
-void AudacityProject::AS_SetRate(double rate)
+void ProjectManager::AS_SetRate(double rate)
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &settings = ProjectSettings::Get( project );
    settings.SetRate( rate );
 }
 
-int AudacityProject::AS_GetSnapTo()
+int ProjectManager::AS_GetSnapTo()
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &settings = ProjectSettings::Get( project );
    return settings.GetSnapTo();
 }
 
-void AudacityProject::AS_SetSnapTo(int snap)
+void ProjectManager::AS_SetSnapTo(int snap)
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &settings = ProjectSettings::Get( project );
+   auto &window = project;
 
    settings.SetSnapTo( snap );
 
@@ -1537,21 +1537,21 @@ void AudacityProject::AS_SetSnapTo(int snap)
 
    SnapSelection();
 
-   RedrawProject();
+   window.RedrawProject();
 
    SelectionBar::Get( project ).SetSnapTo(snap);
 }
 
-const NumericFormatSymbol & AudacityProject::AS_GetSelectionFormat()
+const NumericFormatSymbol & ProjectManager::AS_GetSelectionFormat()
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &settings = ProjectSettings::Get( project );
    return settings.GetSelectionFormat();
 }
 
-void AudacityProject::AS_SetSelectionFormat(const NumericFormatSymbol & format)
+void ProjectManager::AS_SetSelectionFormat(const NumericFormatSymbol & format)
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &settings = ProjectSettings::Get( project );
    settings.SetSelectionFormat( format );
 
@@ -1564,9 +1564,9 @@ void AudacityProject::AS_SetSelectionFormat(const NumericFormatSymbol & format)
    SelectionBar::Get( project ).SetSelectionFormat(format);
 }
 
-double AudacityProject::SSBL_GetRate() const
+double ProjectManager::SSBL_GetRate() const
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &settings = ProjectSettings::Get( project );
    auto &tracks = TrackList::Get( project );
    // Return maximum of project rate and all track rates.
@@ -1574,16 +1574,17 @@ double AudacityProject::SSBL_GetRate() const
       tracks.Any<const WaveTrack>().max( &WaveTrack::GetRate ) );
 }
 
-const NumericFormatSymbol & AudacityProject::SSBL_GetFrequencySelectionFormatName()
+const NumericFormatSymbol & ProjectManager::SSBL_GetFrequencySelectionFormatName()
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &settings = ProjectSettings::Get( project );
    return settings.GetFrequencySelectionFormatName();
 }
 
-void AudacityProject::SSBL_SetFrequencySelectionFormatName(const NumericFormatSymbol & formatName)
+void ProjectManager::SSBL_SetFrequencySelectionFormatName(
+   const NumericFormatSymbol & formatName)
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &settings = ProjectSettings::Get( project );
 
    settings.SetFrequencySelectionFormatName( formatName );
@@ -1597,16 +1598,18 @@ void AudacityProject::SSBL_SetFrequencySelectionFormatName(const NumericFormatSy
 #endif
 }
 
-const NumericFormatSymbol & AudacityProject::SSBL_GetBandwidthSelectionFormatName()
+const NumericFormatSymbol &
+ProjectManager::SSBL_GetBandwidthSelectionFormatName()
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &settings = ProjectSettings::Get( project );
    return settings.GetBandwidthSelectionFormatName();
 }
 
-void AudacityProject::SSBL_SetBandwidthSelectionFormatName(const NumericFormatSymbol & formatName)
+void ProjectManager::SSBL_SetBandwidthSelectionFormatName(
+   const NumericFormatSymbol & formatName)
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &settings = ProjectSettings::Get( project );
 
    settings.SetBandwidthSelectionFormatName( formatName );
@@ -1620,10 +1623,11 @@ void AudacityProject::SSBL_SetBandwidthSelectionFormatName(const NumericFormatSy
 #endif
 }
 
-void AudacityProject::SSBL_ModifySpectralSelection(double &bottom, double &top, bool done)
+void ProjectManager::SSBL_ModifySpectralSelection(
+   double &bottom, double &top, bool done)
 {
 #ifdef EXPERIMENTAL_SPECTRAL_EDITING
-   auto &project = *this;
+   auto &project = mProject;
    auto &trackPanel = TrackPanel::Get( project );
    auto &viewInfo = ViewInfo::Get( project );
 
@@ -1643,9 +1647,9 @@ void AudacityProject::SSBL_ModifySpectralSelection(double &bottom, double &top,
 }
 
 
-void AudacityProject::AS_ModifySelection(double &start, double &end, bool done)
+void ProjectManager::AS_ModifySelection(double &start, double &end, bool done)
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &trackPanel = TrackPanel::Get( project );
    auto &viewInfo = ViewInfo::Get( project );
    viewInfo.selectedRegion.setTimes(start, end);
@@ -2386,9 +2390,9 @@ public:
 //     be deleted before the final mDirManager->Deref() in this
 //     routine.  Failing to do so can cause unwanted recursion
 //     and/or attempts to DELETE objects twice.
-void AudacityProject::OnCloseWindow(wxCloseEvent & event)
+void ProjectManager::OnCloseWindow(wxCloseEvent & event)
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &projectFileIO = project;
    const auto &settings = ProjectSettings::Get( project );
    auto &projectAudioIO = ProjectAudioIO::Get( project );
@@ -2406,7 +2410,7 @@ void AudacityProject::OnCloseWindow(wxCloseEvent & event)
       return;
    }
 
-   if (event.CanVeto() && (::wxIsBusy() || mbBusyImporting))
+   if (event.CanVeto() && (::wxIsBusy() || project.mbBusyImporting))
    {
       event.Veto();
       return;
@@ -2426,9 +2430,9 @@ void AudacityProject::OnCloseWindow(wxCloseEvent & event)
       wxCommandEvent dummyEvent;
       ControlToolBar::Get( project ).OnStop(dummyEvent);
 
-      FixScrollbars();
+      window.FixScrollbars();
       projectAudioIO.SetAudioIOToken(0);
-      RedrawProject();
+      window.RedrawProject();
    }
    else if (gAudioIO->IsMonitoring()) {
       gAudioIO->StopStream();
@@ -2441,7 +2445,7 @@ void AudacityProject::OnCloseWindow(wxCloseEvent & event)
    // project is now empty.
    if (event.CanVeto() && (settings.EmptyCanBeDirty() || bHasTracks)) {
       if ( UndoManager::Get( project ).UnsavedChanges() ) {
-         TitleRestorer Restorer( this );// RAII
+         TitleRestorer Restorer( &window );// RAII
          /* i18n-hint: The first %s numbers the project, the second %s is the project name.*/
          wxString Title =  wxString::Format(_("%sSave changes to %s?"), Restorer.sProjNumber, Restorer.sProjName);
          wxString Message = _("Save project before closing?");
@@ -2452,10 +2456,10 @@ void AudacityProject::OnCloseWindow(wxCloseEvent & event)
          int result = AudacityMessageBox( Message,
                                     Title,
                                    wxYES_NO | wxCANCEL | wxICON_QUESTION,
-                                   this);
+                                   &window);
 
          if (result == wxCANCEL || (result == wxYES &&
-              !GuardedCall<bool>( [&]{ return Save(); } )
+              !GuardedCall<bool>( [&]{ return projectFileIO.Save(); } )
          )) {
             event.Veto();
             return;
@@ -2472,7 +2476,7 @@ void AudacityProject::OnCloseWindow(wxCloseEvent & event)
    // (But is there a different way to do this? What do other applications do?
    //  I don't see full screen windows of Safari shrinking, but I do see
    //  momentary blackness.)
-   ShowFullScreen(false);
+   window.ShowFullScreen(false);
 #endif
 
    ModuleManager::Get().Dispatch(ProjectClosing);
@@ -2482,7 +2486,7 @@ void AudacityProject::OnCloseWindow(wxCloseEvent & event)
 
    // The project is now either saved or the user doesn't want to save it,
    // so there's no need to keep auto save info around anymore
-   DeleteCurrentAutoSaveFile();
+   projectFileIO.DeleteCurrentAutoSaveFile();
 
    // DMM: Save the size of the last window the user closes
    //
@@ -2530,7 +2534,7 @@ void AudacityProject::OnCloseWindow(wxCloseEvent & event)
    // to save the state of the toolbars.
    ToolManager::Get( project ).Destroy();
 
-   DestroyChildren();
+   window.DestroyChildren();
 
    TrackFactory::Destroy( project );
 
@@ -2551,10 +2555,10 @@ void AudacityProject::OnCloseWindow(wxCloseEvent & event)
    DirManager::Destroy( project );
 
    // Remove self from the global array, but defer destruction of self
-   auto pSelf = AllProjects{}.Remove( *this );
+   auto pSelf = AllProjects{}.Remove( project );
    wxASSERT( pSelf );
 
-   if (gActiveProject == this) {
+   if (gActiveProject == &project) {
       // Find a NEW active project
       if ( !AllProjects{}.empty() ) {
          SetActiveProject(AllProjects{}.begin()->get());
@@ -2567,7 +2571,10 @@ void AudacityProject::OnCloseWindow(wxCloseEvent & event)
    // Since we're going to be destroyed, make sure we're not to
    // receive audio notifications anymore.
    if (gAudioIO->GetListener() == this) {
-      gAudioIO->SetListener(gActiveProject);
+      gAudioIO->SetListener( gActiveProject
+         ? &ProjectManager::Get( *gActiveProject )
+         : nullptr
+      );
    }
 
    if (AllProjects{}.empty() && !AllProjects::Closing()) {
@@ -2581,28 +2588,34 @@ void AudacityProject::OnCloseWindow(wxCloseEvent & event)
       else {
          AllProjects::Reset();
          // For non-Mac, always keep at least one project window open
-         CreateNewAudacityProject();
+         (void) New();
       }
 #endif
    }
 
+   window.Destroy();
+
    // Destroys this
    pSelf.reset();
 }
 
-void AudacityProject::OnOpenAudioFile(wxCommandEvent & event)
+// PRL: I preserve this handler function for an event that was never sent, but
+// I don't know the intention.
+
+void ProjectManager::OnOpenAudioFile(wxCommandEvent & event)
 {
+   auto &project = mProject;
+   auto &window = GetProjectFrame( project );
    const wxString &cmd = event.GetString();
 
-   if (!cmd.empty()) {
+   if (!cmd.empty())
       OpenFile(cmd);
-   }
 
-   RequestUserAttention();
+   window.RequestUserAttention();
 }
 
 // static method, can be called outside of a project
-wxArrayString AudacityProject::ShowOpenDialog(const wxString &extraformat, const wxString &extrafilter)
+wxArrayString ProjectManager::ShowOpenDialog(const wxString &extraformat, const wxString &extrafilter)
 {
    FormatList l;
    wxString filter;  ///< List of file format names and extensions, separated
@@ -2707,13 +2720,13 @@ wxArrayString AudacityProject::ShowOpenDialog(const wxString &extraformat, const
 }
 
 // static method, can be called outside of a project
-bool AudacityProject::IsAlreadyOpen(const FilePath &projPathName)
+bool ProjectManager::IsAlreadyOpen(const FilePath &projPathName)
 {
    const wxFileName newProjPathName(projPathName);
    auto start = AllProjects{}.begin(), finish = AllProjects{}.end(),
    iter = std::find_if( start, finish,
       [&]( const AllProjects::value_type &ptr ){
-         return (newProjPathName.SameAs(wxFileNameWrapper{ ptr->mFileName }));
+         return newProjPathName.SameAs(wxFileNameWrapper{ ptr->GetFileName() });
       } );
    if (iter != finish) {
       wxString errMsg =
@@ -2726,14 +2739,22 @@ bool AudacityProject::IsAlreadyOpen(const FilePath &projPathName)
    return false;
 }
 
+const int AudacityProjectTimerID = 5200;
+
+BEGIN_EVENT_TABLE( ProjectManager, wxEvtHandler )
+   EVT_COMMAND(wxID_ANY, EVT_OPEN_AUDIO_FILE, ProjectManager::OnOpenAudioFile)
+   EVT_TIMER(AudacityProjectTimerID, ProjectManager::OnTimer)
+END_EVENT_TABLE()
+
 // static method, can be called outside of a project
-void AudacityProject::OpenFiles(AudacityProject *proj)
+void ProjectManager::OpenFiles(AudacityProject *proj)
 {
    /* i18n-hint: This string is a label in the file type filter in the open
     * and save dialogues, for the option that only shows project files created
     * with Audacity. Do not include pipe symbols or .aup (this extension will
     * now be added automatically for the Save Projects dialogues).*/
-   auto selectedFiles = ShowOpenDialog(_("Audacity projects"), wxT("*.aup"));
+   auto selectedFiles =
+      ProjectManager::ShowOpenDialog(_("Audacity projects"), wxT("*.aup"));
    if (selectedFiles.size() == 0) {
       gPrefs->Write(wxT("/LastOpenType"),wxT(""));
       gPrefs->Flush();
@@ -2755,7 +2776,7 @@ void AudacityProject::OpenFiles(AudacityProject *proj)
       const wxString &fileName = selectedFiles[ff];
 
       // Make sure it isn't already open.
-      if (AudacityProject::IsAlreadyOpen(fileName))
+      if (IsAlreadyOpen(fileName))
          continue; // Skip ones that are already open.
 
       FileNames::UpdateDefaultPath(FileNames::Operation::Open, fileName);
@@ -2770,13 +2791,16 @@ void AudacityProject::OpenFiles(AudacityProject *proj)
       // there are no tracks, but there's an Undo history, etc, then
       // bad things can happen, including data files moving to the NEW
       // project directory, etc.
-      if ( proj && ( proj->mDirty || !TrackList::Get( *proj ).empty() ) )
+      if ( proj && (
+         Get( *proj ).mDirty ||
+         !TrackList::Get( *proj ).empty()
+      ) )
          proj = nullptr;
 
       // This project is clean; it's never been touched.  Therefore
       // all relevant member variables are in their initial state,
       // and it's okay to open a NEW project inside this window.
-      proj = AudacityProject::OpenProject( proj, fileName );
+      proj = OpenProject( proj, fileName );
    }
 }
 
@@ -2807,19 +2831,19 @@ bool AudacityProject::WarnOfLegacyFile( )
 }
 
 
-AudacityProject *AudacityProject::OpenProject(
+AudacityProject *ProjectManager::OpenProject(
    AudacityProject *pProject, const FilePath &fileNameArg, bool addtohistory)
 {
    AudacityProject *pNewProject = nullptr;
    if ( ! pProject )
-      pProject = pNewProject = CreateNewAudacityProject();
+      pProject = pNewProject = New();
    auto cleanup = finally( [&] {
       if( pNewProject )
          GetProjectFrame( *pNewProject ).Close(true);
    } );
-   pProject->OpenFile( fileNameArg, addtohistory );
+   Get( *pProject ).OpenFile( fileNameArg, addtohistory );
    pNewProject = nullptr;
-   if( pProject && pProject->mIsRecovered )
+   if( pProject && pProject->IsRecovered() )
       ProjectWindow::Get( *pProject ).Zoom(
          ViewActions::GetZoomOfToFit( *pProject ) );
 
@@ -2916,8 +2940,9 @@ auto AudacityProject::ReadProjectFile( const FilePath &fileName )
 }
 
 XMLTagHandler *
-AudacityProject::RecordingRecoveryFactory( AudacityProject &project ) {
-   auto &ptr = project.mRecordingRecoveryHandler;
+ProjectManager::RecordingRecoveryFactory( AudacityProject &project ) {
+   auto &projectManager = Get( project );
+   auto &ptr = projectManager.mRecordingRecoveryHandler;
    if (!ptr)
       ptr =
          std::make_unique<RecordingRecoveryHandler>( &project );
@@ -2925,18 +2950,20 @@ AudacityProject::RecordingRecoveryFactory( AudacityProject &project ) {
 }
 
 ProjectFileIORegistry::Entry
-AudacityProject::sRecoveryFactory{
+ProjectManager::sRecoveryFactory{
    wxT("recordingrecovery"), RecordingRecoveryFactory
 };
 
 // FIXME:? TRAP_ERR This should return a result that is checked.
 //    See comment in AudacityApp::MRUOpen().
-void AudacityProject::OpenFile(const FilePath &fileNameArg, bool addtohistory)
+void ProjectManager::OpenFile(const FilePath &fileNameArg, bool addtohistory)
 {
-   auto &project = *this;
+   auto &project = mProject;
+   auto &projectFileIO = project;
    auto &tracks = TrackList::Get( project );
    auto &trackPanel = TrackPanel::Get( project );
    auto &dirManager = DirManager::Get( project );
+   auto &window = ProjectWindow::Get( project );
 
    // On Win32, we may be given a short (DOS-compatible) file name on rare
    // occassions (e.g. stuff like "C:\PROGRA~1\AUDACI~1\PROJEC~1.AUP"). We
@@ -2951,7 +2978,7 @@ void AudacityProject::OpenFile(const FilePath &fileNameArg, bool addtohistory)
    //    then open a NEW project from the same data with no warning.
    //    This was reported in http://bugzilla.audacityteam.org/show_bug.cgi?id=137#c17,
    //    but is not really part of that bug. Anyway, prevent it!
-   if (AudacityProject::IsAlreadyOpen(fileName))
+   if (IsAlreadyOpen(fileName))
       return;
 
 
@@ -2963,7 +2990,7 @@ void AudacityProject::OpenFile(const FilePath &fileNameArg, bool addtohistory)
       AudacityMessageBox(
          _("You are trying to open an automatically created backup file.\nDoing this may result in severe data loss.\n\nPlease open the actual Audacity project file instead."),
          _("Warning - Backup File Detected"),
-         wxOK | wxCENTRE, this);
+         wxOK | wxCENTRE, &window);
       return;
    }
 
@@ -2971,7 +2998,7 @@ void AudacityProject::OpenFile(const FilePath &fileNameArg, bool addtohistory)
       AudacityMessageBox(
          wxString::Format( _("Could not open file: %s"), fileName ),
          ("Error Opening File"),
-         wxOK | wxCENTRE, this);
+         wxOK | wxCENTRE, &window);
       return;
    }
 
@@ -2987,14 +3014,14 @@ void AudacityProject::OpenFile(const FilePath &fileNameArg, bool addtohistory)
          AudacityMessageBox(
             wxString::Format( _("Could not open file: %s"), fileName ),
             _("Error opening file"),
-            wxOK | wxCENTRE, this);
+            wxOK | wxCENTRE, &window);
          return;
       }
       int numRead = ff.Read(buf, 15);
       if (numRead != 15) {
          AudacityMessageBox(wxString::Format(_("File may be invalid or corrupted: \n%s"),
             fileName), _("Error Opening File or Project"),
-            wxOK | wxCENTRE, this);
+            wxOK | wxCENTRE, &window);
          ff.Close();
          return;
       }
@@ -3006,14 +3033,14 @@ void AudacityProject::OpenFile(const FilePath &fileNameArg, bool addtohistory)
    if (temp == wxT("AudacityProject")) {
       // It's an Audacity 1.0 (or earlier) project file.
       // If they bail out, return and do no more.
-      if( !WarnOfLegacyFile() )
+      if( !projectFileIO.WarnOfLegacyFile() )
          return;
       // Convert to the NEW format.
       bool success = ConvertLegacyProjectFile(wxFileName{ fileName });
       if (!success) {
          AudacityMessageBox(_("Audacity was unable to convert an Audacity 1.0 project to the new project format."),
                       _("Error Opening Project"),
-                      wxOK | wxCENTRE, this);
+                      wxOK | wxCENTRE, &window);
          return;
       }
       else {
@@ -3037,12 +3064,12 @@ void AudacityProject::OpenFile(const FilePath &fileNameArg, bool addtohistory)
       {
 #ifdef USE_MIDI
          if (Importer::IsMidi(fileName))
-            FileActions::DoImportMIDI(this, fileName);
+            FileActions::DoImportMIDI( &project, fileName );
          else
 #endif
-            Import(fileName);
+            Import( fileName );
 
-         ZoomAfterImport(nullptr);
+         window.ZoomAfterImport(nullptr);
       }
 
       return;
@@ -3055,7 +3082,7 @@ void AudacityProject::OpenFile(const FilePath &fileNameArg, bool addtohistory)
       mRecordingRecoveryHandler.reset();
    } );
 
-   auto results = ReadProjectFile( fileName );
+   auto results = projectFileIO.ReadProjectFile( fileName );
 
    if ( results.decodeError )
       return;
@@ -3075,7 +3102,7 @@ void AudacityProject::OpenFile(const FilePath &fileNameArg, bool addtohistory)
 
       InitialState();
       trackPanel.SetFocusedTrack( *tracks.Any().begin() );
-      HandleResize();
+      window.HandleResize();
       trackPanel.Refresh(false);
       trackPanel.Update(); // force any repaint to happen now,
       // else any asynch calls into the blockfile code will not have
@@ -3096,19 +3123,19 @@ void AudacityProject::OpenFile(const FilePath &fileNameArg, bool addtohistory)
          if ( bParseSuccess ) {
             // This is a no-fail:
             dirManager.FillBlockfilesCache();
-            EnqueueODTasks();
+            projectFileIO.EnqueueODTasks();
          }
 
          // For an unknown reason, OSX requires that the project window be
          // raised if a recovery took place.
-         CallAfter( [this] { Raise(); } );
+         window.CallAfter( [&] { window.Raise(); } );
       }
    } );
    
    if (bParseSuccess) {
       bool saved = false;
 
-      if (mIsRecovered)
+      if (projectFileIO.IsRecovered())
       {
          // This project has been recovered, so write a NEW auto-save file
          // now and then DELETE the old one in the auto-save folder. Note that
@@ -3118,11 +3145,11 @@ void AudacityProject::OpenFile(const FilePath &fileNameArg, bool addtohistory)
          ::ProjectFSCK(dirManager, err, true); // Correct problems in auto-recover mode.
 
          // PushState calls AutoSave(), so no longer need to do so here.
-         this->PushState(_("Project was recovered"), _("Recover"));
+         PushState(_("Project was recovered"), _("Recover"));
 
          if (!wxRemoveFile(fileName))
             AudacityMessageBox(_("Could not remove old auto save file"),
-                         _("Error"), wxICON_STOP, this);
+                         _("Error"), wxICON_STOP, &window);
       }
       else
       {
@@ -3146,7 +3173,7 @@ void AudacityProject::OpenFile(const FilePath &fileNameArg, bool addtohistory)
                */
             closed = true;
             SetMenuClose(true);
-            Close();
+            window.Close();
             return;
          }
          else if (status & FSCKstatus_CHANGED)
@@ -3164,7 +3191,7 @@ void AudacityProject::OpenFile(const FilePath &fileNameArg, bool addtohistory)
             //    this->PushState(_("Project checker repaired file"), _("Project Repair"));
 
             if (status & FSCKstatus_SAVE_AUP)
-               this->Save(), saved = true;
+               projectFileIO.Save(), saved = true;
          }
       }
 
@@ -3172,7 +3199,7 @@ void AudacityProject::OpenFile(const FilePath &fileNameArg, bool addtohistory)
          if (!saved)
             // We processed an <import> tag, so save it as a normal project,
             // with no <import> tags.
-            this->Save();
+            projectFileIO.Save();
       }
    }
    else {
@@ -3191,8 +3218,8 @@ void AudacityProject::OpenFile(const FilePath &fileNameArg, bool addtohistory)
 
       tracks.Clear(); //tracks.Clear(true);
 
-      mFileName = wxT("");
-      SetProjectTitle();
+      project.SetFileName( wxT("") );
+      projectFileIO.SetProjectTitle();
 
       wxLogError(wxT("Could not parse file \"%s\". \nError: %s"), fileName, errorStr);
 
@@ -3257,7 +3284,7 @@ void AudacityProject::OpenFile(const FilePath &fileNameArg, bool addtohistory)
 */
 
       ShowErrorDialog(
-         this,
+         &window,
          _("Error Opening Project"),
          errorStr,
          url);
@@ -4095,10 +4122,11 @@ bool AudacityProject::SaveCopyWaveTracks(const FilePath & strProjectPathName,
 
 
 std::vector< std::shared_ptr< Track > >
-AudacityProject::AddImportedTracks(const FilePath &fileName,
+ProjectManager::AddImportedTracks(const FilePath &fileName,
                                    TrackHolders &&newTracks)
 {
-   auto &project = *this;
+   auto &project = mProject;
+   auto &projectFileIO = project;
    auto &tracks = TrackList::Get( project );
 
    std::vector< std::shared_ptr< Track > > results;
@@ -4160,7 +4188,7 @@ AudacityProject::AddImportedTracks(const FilePath &fileName,
                SeqBlock& block = blocks[0];
                if (block.f->IsAlias())
                {
-                  mImportedDependencies = true;
+                  projectFileIO.SetImportedDependencies( true );
                }
             }
          }
@@ -4176,7 +4204,7 @@ AudacityProject::AddImportedTracks(const FilePath &fileName,
    }
 
    PushState(wxString::Format(_("Imported '%s'"), fileName),
-             _("Import"));
+       _("Import"));
 
 #if defined(__WXGTK__)
    // See bug #1224
@@ -4187,11 +4215,12 @@ AudacityProject::AddImportedTracks(const FilePath &fileName,
    wxEventLoopBase::GetActive()->YieldFor(wxEVT_CATEGORY_UI | wxEVT_CATEGORY_USER_INPUT);
 #endif
 
-   if (initiallyEmpty && !IsProjectSaved() ) {
+   if (initiallyEmpty && !projectFileIO.IsProjectSaved() ) {
       wxString name = fileName.AfterLast(wxFILE_SEP_PATH).BeforeLast(wxT('.'));
-      mFileName =::wxPathOnly(fileName) + wxFILE_SEP_PATH + name + wxT(".aup");
-      mbLoadedFromAup = false;
-      SetProjectTitle();
+      project.SetFileName(
+         ::wxPathOnly(fileName) + wxFILE_SEP_PATH + name + wxT(".aup") );
+      projectFileIO.SetLoadedFromAup( false );
+      projectFileIO.SetProjectTitle();
    }
 
    // Moved this call to higher levels to prevent flicker redrawing everything on each file.
@@ -4215,9 +4244,10 @@ void AudacityProject::ZoomAfterImport(Track *pTrack)
 }
 
 // If pNewTrackList is passed in non-NULL, it gets filled with the pointers to NEW tracks.
-bool AudacityProject::Import(const FilePath &fileName, WaveTrackArray* pTrackArray /*= NULL*/)
+bool ProjectManager::Import(
+   const FilePath &fileName, WaveTrackArray* pTrackArray /*= NULL*/)
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &dirManager = DirManager::Get( project );
    auto oldTags = Tags::Get( project ).shared_from_this();
    TrackHolders newTracks;
@@ -4242,7 +4272,7 @@ bool AudacityProject::Import(const FilePath &fileName, WaveTrackArray* pTrackArr
       if (!errorMessage.empty()) {
          // Error message derived from Importer::Import
          // Additional help via a Help button links to the manual.
-         ShowErrorDialog(this, _("Error Importing"),
+         ShowErrorDialog(&GetProjectFrame( project ), _("Error Importing"),
                          errorMessage, wxT("Importing_Audio"));
       }
       if (!success)
@@ -4520,9 +4550,9 @@ will be irreversibly overwritten."), fName, fName);
 // Undo/History methods
 //
 
-void AudacityProject::InitialState()
+void ProjectManager::InitialState()
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &tracks = TrackList::Get( project );
    auto &viewInfo = ViewInfo::Get( project );
    auto &undoManager = UndoManager::Get( project );
@@ -4541,34 +4571,35 @@ void AudacityProject::InitialState()
    menuManager.UpdateMenus( project );
 }
 
-bool AudacityProject::UndoAvailable()
+bool ProjectManager::UndoAvailable()
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &tracks = TrackList::Get( project );
    auto &undoManager = UndoManager::Get( project );
    return undoManager.UndoAvailable() &&
        !tracks.HasPendingTracks();
 }
 
-bool AudacityProject::RedoAvailable()
+bool ProjectManager::RedoAvailable()
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &tracks = TrackList::Get( project );
    auto &undoManager = UndoManager::Get( project );
    return undoManager.RedoAvailable() &&
       !tracks.HasPendingTracks();
 }
 
-void AudacityProject::PushState(const wxString &desc, const wxString &shortDesc)
+void ProjectManager::PushState(const wxString &desc, const wxString &shortDesc)
 {
    PushState(desc, shortDesc, UndoPush::AUTOSAVE);
 }
 
-void AudacityProject::PushState(const wxString &desc,
+void ProjectManager::PushState(const wxString &desc,
                                 const wxString &shortDesc,
                                 UndoPush flags )
 {
-   auto &project = *this;
+   auto &project = mProject;
+   auto &projectFileIO = project;
    const auto &settings = ProjectSettings::Get( project );
    auto &tracks = TrackList::Get( project );
    auto &viewInfo = ViewInfo::Get( project );
@@ -4587,21 +4618,22 @@ void AudacityProject::PushState(const wxString &desc,
    if (settings.GetTracksFitVerticallyZoomed())
       ViewActions::DoZoomFitV( project );
    if((flags & UndoPush::AUTOSAVE) != UndoPush::MINIMAL)
-      AutoSave();
+      projectFileIO.AutoSave();
 
    TrackPanel::Get( project ).HandleCursorForPresentMouseState();
 }
 
-void AudacityProject::RollbackState()
+void ProjectManager::RollbackState()
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &undoManager = UndoManager::Get( project );
    SetStateTo( undoManager.GetCurrentState() );
 }
 
-void AudacityProject::ModifyState(bool bWantsAutoSave)
+void ProjectManager::ModifyState(bool bWantsAutoSave)
 {
-   auto &project = *this;
+   auto &project = mProject;
+   auto &projectFileIO = project;
    auto &tracks = TrackList::Get( project );
    auto &viewInfo = ViewInfo::Get( project );
    auto &undoManager = UndoManager::Get( project );
@@ -4609,18 +4641,20 @@ void AudacityProject::ModifyState(bool bWantsAutoSave)
    undoManager.ModifyState(
       &tracks, viewInfo.selectedRegion, tags.shared_from_this());
    if (bWantsAutoSave)
-      AutoSave();
+      projectFileIO.AutoSave();
    TrackPanel::Get( project ).HandleCursorForPresentMouseState();
 }
 
 // LL:  Is there a memory leak here as "l" and "t" are not deleted???
 // Vaughan, 2010-08-29: No, as "l" is a TrackList* of an Undo stack state.
 //    Need to keep it and its tracks "t" available for Undo/Redo/SetStateTo.
-void AudacityProject::PopState(const UndoState &state)
+void ProjectManager::PopState(const UndoState &state)
 {
-   auto &project = *this;
+   auto &project = mProject;
+   auto &projectFileIO = project;
    auto &dstTracks = TrackList::Get( project );
    auto &viewInfo = ViewInfo::Get( project );
+   auto &window = ProjectWindow::Get( project );
 
    viewInfo.selectedRegion = state.selectedRegion;
 
@@ -4665,22 +4699,24 @@ void AudacityProject::PopState(const UndoState &state)
    if(odUsed)
       ODManager::Instance()->AddNewTask(std::move(computeTask));
 
-   HandleResize();
+   window.HandleResize();
 
    MenuManager::Get( project ).UpdateMenus( project );
 
-   AutoSave();
+   projectFileIO.AutoSave();
 }
 
-void AudacityProject::SetStateTo(unsigned int n)
+void ProjectManager::SetStateTo(unsigned int n)
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &trackPanel = TrackPanel::Get( project );
    auto &undoManager = UndoManager::Get( project );
+   auto &window = ProjectWindow::Get( project );
+
    undoManager.SetStateTo(n,
       [this]( const UndoState &state ){ PopState(state); } );
 
-   HandleResize();
+   window.HandleResize();
    trackPanel.SetFocusedTrack(NULL);
    trackPanel.Refresh(false);
    MenuManager::Get( project ).ModifyUndoMenuItems( project );
@@ -4760,7 +4796,7 @@ void AudacityProject::SkipEnd(bool shift)
 }
 
 
-void AudacityProject::RestartTimer()
+void ProjectManager::RestartTimer()
 {
    if (mTimer) {
       // mTimer->Stop(); // not really needed
@@ -4768,14 +4804,16 @@ void AudacityProject::RestartTimer()
    }
 }
 
-void AudacityProject::OnTimer(wxTimerEvent& WXUNUSED(event))
+void ProjectManager::OnTimer(wxTimerEvent& WXUNUSED(event))
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &projectAudioIO = ProjectAudioIO::Get( project );
-   auto &window = project;
+   auto &window = GetProjectFrame( project );
    auto &dirManager = DirManager::Get( project );
    auto mixerToolBar = &MixerToolBar::Get( project );
    mixerToolBar->UpdateControls();
+   
+   auto &statusBar = *window.GetStatusBar();
 
    // gAudioIO->GetNumCaptureChannels() should only be positive
    // when we are recording.
@@ -4788,7 +4826,7 @@ void AudacityProject::OnTimer(wxTimerEvent& WXUNUSED(event))
          sMessage.Printf(_("Disk space remaining for recording: %s"), GetHoursMinsString(iRecordingMins));
 
          // Do not change mLastMainStatusMessage
-         window.GetStatusBar()->SetStatusText(sMessage, mainStatusBarField);
+         statusBar.SetStatusText(sMessage, mainStatusBarField);
       }
    }
    else if(ODManager::IsInstanceCreated())
@@ -4809,7 +4847,7 @@ void AudacityProject::OnTimer(wxTimerEvent& WXUNUSED(event))
 
 
             msg = _("On-demand import and waveform calculation complete.");
-            window.GetStatusBar()->SetStatusText(msg, mainStatusBarField);
+            statusBar.SetStatusText(msg, mainStatusBarField);
 
          }
          else if(numTasks>1)
@@ -4820,7 +4858,7 @@ void AudacityProject::OnTimer(wxTimerEvent& WXUNUSED(event))
              ratioComplete*100.0);
 
 
-         window.GetStatusBar()->SetStatusText(msg, mainStatusBarField);
+         statusBar.SetStatusText(msg, mainStatusBarField);
       }
    }
 
@@ -4840,9 +4878,9 @@ void AudacityProject::SetStatus(const wxString &msg)
    }
 }
 
-void AudacityProject::OnStatusChange( wxCommandEvent & )
+void ProjectManager::OnStatusChange( wxCommandEvent & )
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &window = project;
    const auto &msg = project.GetStatus();
    window.GetStatusBar()->SetStatusText(msg, mainStatusBarField);
@@ -4991,9 +5029,9 @@ void AudacityProject::DeleteCurrentAutoSaveFile()
 }
 
 
-void AudacityProject::OnAudioIORate(int rate)
+void ProjectManager::OnAudioIORate(int rate)
 {
-   auto &project = *this;
+   auto &project = mProject;
    auto &window = GetProjectFrame( project );
    wxString display;
    if (rate > 0) {
@@ -5016,19 +5054,21 @@ void AudacityProject::OnAudioIORate(int rate)
    statusBar->SetStatusText(display, rateStatusBarField);
 }
 
-void AudacityProject::OnAudioIOStartRecording()
+void ProjectManager::OnAudioIOStartRecording()
 {
+   auto &projectFileIO = mProject;
    // Before recording is started, auto-save the file. The file will have
    // empty tracks at the bottom where the recording will be put into
-   AutoSave();
+   projectFileIO.AutoSave();
 }
 
 // This is called after recording has stopped and all tracks have flushed.
-void AudacityProject::OnAudioIOStopRecording()
+void ProjectManager::OnAudioIOStopRecording()
 {
-   auto &project = *this;
-   auto &projectAudioIO = ProjectAudioIO::Get( project );
+   auto &project = mProject;
    auto &dirManager = DirManager::Get( project );
+   auto &projectAudioIO = ProjectAudioIO::Get( project );
+   auto &projectFileIO = project;
    auto &window = ProjectWindow::Get( project );
 
    // Only push state if we were capturing and not monitoring
@@ -5072,7 +5112,7 @@ You are saving directly to a slow external storage device\n\
       // Reset timer record 
       if (IsTimerRecordCancelled())
       {
-         EditActions::DoUndo( *this );
+         EditActions::DoUndo( project );
          ResetTimerRecordCancelled();
       }
 
@@ -5085,15 +5125,19 @@ You are saving directly to a slow external storage device\n\
    dirManager.WriteCacheToDisk();
 
    // Now we auto-save again to get the project to a "normal" state again.
-   AutoSave();
+   projectFileIO.AutoSave();
 }
 
-void AudacityProject::OnAudioIONewBlockFiles(const AutoSaveFile & blockFileLog)
+void ProjectManager::OnAudioIONewBlockFiles(
+   const AutoSaveFile & blockFileLog)
 {
+   auto &project = mProject;
+   auto &projectFileIO = project;
    // New blockfiles have been created, so add them to the auto-save file
-   if (!mAutoSaveFileName.empty())
+   const auto &autoSaveFileName = projectFileIO.GetAutoSaveFileName();
+   if ( !autoSaveFileName.empty() )
    {
-      wxFFile f(mAutoSaveFileName, wxT("ab"));
+      wxFFile f{ autoSaveFileName, wxT("ab") };
       if (!f.IsOpened())
          return; // Keep recording going, there's not much we can do here
       blockFileLog.Append(f);
@@ -5111,8 +5155,8 @@ bool AudacityProject::IsProjectSaved() {
 }
 
 // This is done to empty out the tracks, but without creating a new project.
-void AudacityProject::ResetProjectToEmpty() {
-   auto &project = *this;
+void ProjectManager::ResetProjectToEmpty() {
+   auto &project = mProject;
    auto &projectFileIO = project;
    auto &viewInfo = ViewInfo::Get( project );
 
@@ -5185,7 +5229,7 @@ bool AudacityProject::SaveFromTimerRecording(wxFileName fnFile) {
    return bSuccess;
 }
 
-wxString AudacityProject::GetHoursMinsString(int iMinutes)
+wxString ProjectManager::GetHoursMinsString(int iMinutes)
 {
 
    wxString sFormatted;
@@ -5214,8 +5258,8 @@ wxString AudacityProject::GetHoursMinsString(int iMinutes)
 // minutes of recording time we have available.
 // The calculations made are based on the user's current
 // preferences.
-int AudacityProject::GetEstimatedRecordingMinsLeftOnDisk(long lCaptureChannels) {
-   auto &project = *this;
+int ProjectManager::GetEstimatedRecordingMinsLeftOnDisk(long lCaptureChannels) {
+   auto &project = mProject;
 
    // Obtain the current settings
    auto oCaptureFormat = QualityPrefs::SampleFormatChoice();
@@ -5416,3 +5460,31 @@ void AudacityProject::CloseLock()
       mLastSavedTracks.reset();
    }
 }
+
+static AudacityProject::AttachedObjects::RegisteredFactory sProjectManagerKey {
+   []( AudacityProject &project ) {
+      return std::make_shared< ProjectManager >( project );
+   }
+};
+
+ProjectManager &ProjectManager::Get( AudacityProject &project )
+{
+   return project.AttachedObjects::Get< ProjectManager >( sProjectManagerKey );
+}
+
+const ProjectManager &ProjectManager::Get( const AudacityProject &project )
+{
+   return Get( const_cast< AudacityProject & >( project ) );
+}
+
+ProjectManager::ProjectManager( AudacityProject &project )
+   : mProject{ project }
+   , mTimer{ std::make_unique<wxTimer>(this, AudacityProjectTimerID) }
+{
+   auto &window = ProjectWindow::Get( mProject );
+   window.Bind( wxEVT_CLOSE_WINDOW, &ProjectManager::OnCloseWindow, this );
+   mProject.Bind(EVT_PROJECT_STATUS_UPDATE,
+      &ProjectManager::OnStatusChange, this);
+}
+
+ProjectManager::~ProjectManager() = default;
diff --git a/src/Project.h b/src/Project.h
index 68f640400..d350a9bfb 100644
--- a/src/Project.h
+++ b/src/Project.h
@@ -35,8 +35,6 @@
 
 #include "xml/XMLTagHandler.h" // to inherit
 
-const int AudacityProjectTimerID = 5200;
-
 wxDECLARE_EXPORTED_EVENT(AUDACITY_DLL_API,
                          EVT_PROJECT_STATUS_UPDATE, wxCommandEvent);
 
@@ -61,7 +59,6 @@ struct UndoState;
 enum class UndoPush : unsigned char;
 
 
-AudacityProject *CreateNewAudacityProject();
 AUDACITY_DLL_API AudacityProject *GetActiveProject();
 
 void GetDefaultWindowRect(wxRect *defRect);
@@ -165,10 +162,7 @@ using AttachedWindows = ClientData::Site<
 using ProjectWindow = AudacityProject;
 class AUDACITY_DLL_API AudacityProject final : public wxFrame,
                                      public TrackPanelListener,
-                                     public SelectionBarListener,
-                                     public SpectralSelectionBarListener,
                                      public XMLTagHandler,
-                                     public AudioIOListener,
                                      private PrefsListener
    , public AttachedObjects
    , public AttachedWindows
@@ -200,47 +194,6 @@ class AUDACITY_DLL_API AudacityProject final : public wxFrame,
 
    bool IsActive() override;
 
-   // File I/O
-
-   /** @brief Show an open dialogue for opening audio files, and possibly other
-    * sorts of files.
-    *
-    * The file type filter will automatically contain:
-    * - "All files" with any extension or none,
-    * - "All supported files" based on the file formats supported in this
-    *   build of Audacity,
-    * - All of the individual formats specified by the importer plug-ins which
-    *   are built into this build of Audacity, each with the relevant file
-    *   extensions for that format.
-    * The dialogue will start in the DefaultOpenPath directory read from the
-    * preferences, failing that the working directory. The file format filter
-    * will be set to the DefaultOpenType from the preferences, failing that
-    * the first format specified in the dialogue. These two parameters will
-    * be saved to the preferences once the user has chosen a file to open.
-    * @param extraformat Specify the name of an additional format to allow
-    * opening in this dialogue. This string is free-form, but should be short
-    * enough to fit in the file dialogue filter drop-down. It should be
-    * translated.
-    * @param extrafilter Specify the file extension(s) for the additional format
-    * specified by extraformat. The patterns must include the wildcard (e.g.
-    * "*.aup" not "aup" or ".aup"), separate multiple patters with a semicolon,
-    * e.g. "*.aup;*.AUP" because patterns are case-sensitive. Do not add a
-    * trailing semicolon to the string. This string should not be translated
-    * @return Array of file paths which the user selected to open (multiple
-    * selections allowed).
-    */
-   static wxArrayString ShowOpenDialog(const wxString &extraformat = {},
-         const wxString &extrafilter = {});
-   static bool IsAlreadyOpen(const FilePath &projPathName);
-   static void OpenFiles(AudacityProject *proj);
-
-   // Return the given project if that is not NULL, else create a project.
-   // Then open the given project path.
-   // But if an exception escapes this function, create no NEW project.
-   static AudacityProject *OpenProject(
-      AudacityProject *pProject,
-      const FilePath &fileNameArg, bool addtohistory = true);
-
    struct ReadProjectResults
    {
       bool decodeError;
@@ -250,26 +203,14 @@ class AUDACITY_DLL_API AudacityProject final : public wxFrame,
    };
    ReadProjectResults ReadProjectFile( const FilePath &fileName );
 
-   void OpenFile(const FilePath &fileName, bool addtohistory = true);
-
-private:
    void EnqueueODTasks();
 
-public:
    using wxFrame::DetachMenuBar;
 
    bool WarnOfLegacyFile( );
 
-   // If pNewTrackList is passed in non-NULL, it gets filled with the pointers to NEW tracks.
-   bool Import(const FilePath &fileName, WaveTrackArray *pTrackArray = NULL);
-
    void ZoomAfterImport(Track *pTrack);
 
-   // Takes array of unique pointers; returns array of shared
-   std::vector< std::shared_ptr<Track> >
-   AddImportedTracks(const FilePath &fileName,
-                     TrackHolders &&newTracks);
-
    void CloseLock();
 
    bool Save();
@@ -283,7 +224,9 @@ private:
 public:
 
    const FilePath &GetFileName() { return mFileName; }
-   bool GetDirty() { return mDirty; }
+   void SetFileName( const FilePath &value ) { mFileName = value; }
+
+   const FilePath &GetAutoSaveFileName() { return mAutoSaveFileName; }
    void SetProjectTitle( int number =-1);
 
    wxWindow *GetMainPage() { return mMainPage; }
@@ -292,13 +235,8 @@ public:
    // Timer Record Auto Save/Export Routines
    bool SaveFromTimerRecording(wxFileName fnFile);
    bool IsProjectSaved();
-   void ResetProjectToEmpty();
-   void ResetProjectFileIO();
 
-   // Routine to estimate how many minutes of recording time are left on disk
-   int GetEstimatedRecordingMinsLeftOnDisk(long lCaptureChannels = 0);
-   // Converts number of minutes to human readable format
-   wxString GetHoursMinsString(int iMinutes);
+   void ResetProjectFileIO();
 
 
    // Message Handlers
@@ -316,10 +254,7 @@ public:
    void OnMove(wxMoveEvent & event);
    void DoScroll();
    void OnScroll(wxScrollEvent & event);
-   void OnCloseWindow(wxCloseEvent & event);
-   void OnTimer(wxTimerEvent & event);
    void OnToolBarUpdate(wxCommandEvent & event);
-   void OnOpenAudioFile(wxCommandEvent & event);
 
    void HandleResize();
    void UpdateLayout();
@@ -369,35 +304,7 @@ public:
    const wxString &GetStatus() const { return mLastMainStatusMessage; }
    void SetStatus(const wxString &msg);
 
-   void OnStatusChange( wxCommandEvent& );
-
-private:
-   bool SnapSelection();
-
 public:
-   // SelectionBarListener callback methods
-
-   double AS_GetRate() override;
-   void AS_SetRate(double rate) override;
-   int AS_GetSnapTo() override;
-   void AS_SetSnapTo(int snap) override;
-   const NumericFormatSymbol & AS_GetSelectionFormat() override;
-   void AS_SetSelectionFormat(const NumericFormatSymbol & format) override;
-   void AS_ModifySelection(double &start, double &end, bool done) override;
-
-   // SpectralSelectionBarListener callback methods
-
-   double SSBL_GetRate() const override;
-
-   const NumericFormatSymbol & SSBL_GetFrequencySelectionFormatName() override;
-   void SSBL_SetFrequencySelectionFormatName(const NumericFormatSymbol & formatName) override;
-
-   const NumericFormatSymbol & SSBL_GetBandwidthSelectionFormatName() override;
-   void SSBL_SetBandwidthSelectionFormatName(const NumericFormatSymbol & formatName) override;
-
-   void SSBL_ModifySpectralSelection(double &bottom, double &top, bool done) override;
-
-   void SetStateTo(unsigned int n);
 
    // XMLTagHandler callback methods
 
@@ -408,32 +315,13 @@ public:
 
    void WriteXMLHeader(XMLWriter &xmlFile) const;
 
-   // Audio IO callback methods
-   void OnAudioIORate(int rate) override;
-   void OnAudioIOStartRecording() override;
-   void OnAudioIOStopRecording() override;
-   void OnAudioIONewBlockFiles(const AutoSaveFile & blockFileLog) override;
-
-   bool UndoAvailable();
-   bool RedoAvailable();
-
-   void PushState(const wxString &desc, const wxString &shortDesc); // use UndoPush::AUTOSAVE
-   void PushState(const wxString &desc, const wxString &shortDesc, UndoPush flags);
-   void RollbackState();
-
-
  private:
 
    void OnThemeChange(wxCommandEvent & evt);
-   void InitialState();
 
  public:
-   void ModifyState(bool bWantsAutoSave);    // if true, writes auto-save file. Should set only if you really want the state change restored after
-                                             // a crash, as it can take many seconds for large (eg. 10 track-hours) projects
-
-   void PopState(const UndoState &state);
-
    void AutoSave();
+
    void DeleteCurrentAutoSaveFile();
 
  private:
@@ -448,13 +336,10 @@ public:
    std::shared_ptr<TrackList> mLastSavedTracks;
 
 private:
-   bool mDirty{ false };
 
    // Window elements
 
    wxString mLastMainStatusMessage;
-   std::unique_ptr<wxTimer> mTimer;
-   void RestartTimer();
 
    wxPanel *mTopPanel{};
    wxWindow * mMainPage;
@@ -481,24 +366,21 @@ private:
    void SetNormalizedWindowState(wxRect pSizeAndLocation) {  mNormalizedWindowState = pSizeAndLocation;   }
    wxRect GetNormalizedWindowState() const { return mNormalizedWindowState;   }
 
-   bool IsTimerRecordCancelled(){return mTimerRecordCanceled;}
-   void SetTimerRecordCancelled(){mTimerRecordCanceled=true;}
-   void ResetTimerRecordCancelled(){mTimerRecordCanceled=false;}
-
  private:
    bool mIsDeleting{ false };
 
 public:
    bool IsBeingDeleted() const { return mIsDeleting; }
    void SetIsBeingDeleted() { mIsDeleting = true; }
+   bool IsRecovered() const { return mIsRecovered; }
+   void SetImportedDependencies( bool value ) { mImportedDependencies = value; }
+   void SetLoadedFromAup( bool value ) { mbLoadedFromAup = value; }
 private:
 
    bool mLockPlayRegion;
 
-   std::unique_ptr<ImportXMLTagHandler> mImportXMLTagHandler;
-
    // Last auto-save file name and path (empty if none)
-   wxString mAutoSaveFileName;
+   FilePath mAutoSaveFileName;
 
    // Are we currently auto-saving or not?
    bool mAutoSaving{ false };
@@ -509,9 +391,6 @@ private:
    // The auto-save data dir the project has been recovered from
    wxString mRecoveryAutoSaveDataDir;
 
-   // The handler that handles recovery of <recordingrecovery> tags
-   std::unique_ptr<RecordingRecoveryHandler> mRecordingRecoveryHandler;
-
    // Dependencies have been imported and a warning should be shown on save
    bool mImportedDependencies{ false };
 
@@ -519,16 +398,6 @@ private:
 
    wxRect mNormalizedWindowState;
 
-   //flag for cancellation of timer record.
-   bool mTimerRecordCanceled{ false  };
-
-   // Are we currently closing as the result of a menu command?
-   bool mMenuClose{ false };
-
-public:
-   void SetMenuClose(bool value) { mMenuClose = value; }
-
-private:
    bool mbInitializingScrollbar{ false };
 
 public:
@@ -560,14 +429,175 @@ public:
 private:
    std::unique_ptr<PlaybackScroller> mPlaybackScroller;
 
+public:
+   PlaybackScroller &GetPlaybackScroller() { return *mPlaybackScroller; }
+
+   DECLARE_EVENT_TABLE()
+};
+
+class ProjectManager final
+   : public wxEvtHandler
+   , public ClientData::Base
+   , public AudioIOListener
+   , private SelectionBarListener
+   , private SpectralSelectionBarListener
+{
+public:
+   static ProjectManager &Get( AudacityProject &project );
+   static const ProjectManager &Get( const AudacityProject &project );
+
+   explicit ProjectManager( AudacityProject &project );
+   ~ProjectManager() override;
+
+   // This is the factory for projects:
+   static AudacityProject *New();
+
+   // File I/O
+
+   /** @brief Show an open dialogue for opening audio files, and possibly other
+    * sorts of files.
+    *
+    * The file type filter will automatically contain:
+    * - "All files" with any extension or none,
+    * - "All supported files" based on the file formats supported in this
+    *   build of Audacity,
+    * - All of the individual formats specified by the importer plug-ins which
+    *   are built into this build of Audacity, each with the relevant file
+    *   extensions for that format.
+    * The dialogue will start in the DefaultOpenPath directory read from the
+    * preferences, failing that the working directory. The file format filter
+    * will be set to the DefaultOpenType from the preferences, failing that
+    * the first format specified in the dialogue. These two parameters will
+    * be saved to the preferences once the user has chosen a file to open.
+    * @param extraformat Specify the name of an additional format to allow
+    * opening in this dialogue. This string is free-form, but should be short
+    * enough to fit in the file dialogue filter drop-down. It should be
+    * translated.
+    * @param extrafilter Specify the file extension(s) for the additional format
+    * specified by extraformat. The patterns must include the wildcard (e.g.
+    * "*.aup" not "aup" or ".aup"), separate multiple patters with a semicolon,
+    * e.g. "*.aup;*.AUP" because patterns are case-sensitive. Do not add a
+    * trailing semicolon to the string. This string should not be translated
+    * @return Array of file paths which the user selected to open (multiple
+    * selections allowed).
+    */
+   static wxArrayString ShowOpenDialog(const wxString &extraformat = {},
+         const wxString &extrafilter = {});
+
+   static bool IsAlreadyOpen(const FilePath &projPathName);
+
+   // The functions that open and import files can act as factories too, and
+   // they set projects to initial state.
+   static void OpenFiles(AudacityProject *proj);
+   
+   void OpenFile(const FilePath &fileName, bool addtohistory = true);
+
+   // Return the given project if that is not NULL, else create a project.
+   // Then open the given project path.
+   // But if an exception escapes this function, create no NEW project.
+   static AudacityProject *OpenProject(
+      AudacityProject *pProject,
+      const FilePath &fileNameArg, bool addtohistory = true);
+
+   // If pNewTrackList is passed in non-NULL, it gets filled with the pointers to NEW tracks.
+   bool Import(const FilePath &fileName, WaveTrackArray *pTrackArray = NULL);
+
+   // Takes array of unique pointers; returns array of shared
+   std::vector< std::shared_ptr<Track> >
+   AddImportedTracks(const FilePath &fileName,
+                     TrackHolders &&newTracks);
+
+   bool GetDirty() { return mDirty; }
+
+   void ResetProjectToEmpty();
+
+   // Routine to estimate how many minutes of recording time are left on disk
+   int GetEstimatedRecordingMinsLeftOnDisk(long lCaptureChannels = 0);
+   // Converts number of minutes to human readable format
+   wxString GetHoursMinsString(int iMinutes);
+
+   void SetStateTo(unsigned int n);
+   bool UndoAvailable();
+   bool RedoAvailable();
+   void PushState(const wxString &desc, const wxString &shortDesc); // use UndoPush::AUTOSAVE
+   void PushState(const wxString &desc, const wxString &shortDesc, UndoPush flags);
+   void RollbackState();
+   void ModifyState(bool bWantsAutoSave);    // if true, writes auto-save file.
+      // Should set only if you really want the state change restored after
+      // a crash, as it can take many seconds for large (eg. 10 track-hours)
+      // projects
+   void PopState(const UndoState &state);
+
+   bool IsTimerRecordCancelled() { return mTimerRecordCanceled; }
+   void SetTimerRecordCancelled() { mTimerRecordCanceled = true; }
+   void ResetTimerRecordCancelled() { mTimerRecordCanceled = false; }
+
+   void SetMenuClose(bool value) { mMenuClose = value; }
+
+   // SelectionBarListener callback methods
+   double AS_GetRate() override;
+   void AS_SetRate(double rate) override;
+   int AS_GetSnapTo() override;
+   void AS_SetSnapTo(int snap) override;
+   const NumericFormatSymbol & AS_GetSelectionFormat() override;
+   void AS_SetSelectionFormat(const NumericFormatSymbol & format) override;
+   void AS_ModifySelection(double &start, double &end, bool done) override;
+
+   // SpectralSelectionBarListener callback methods
+   double SSBL_GetRate() const override;
+   const NumericFormatSymbol & SSBL_GetFrequencySelectionFormatName() override;
+   void SSBL_SetFrequencySelectionFormatName(
+      const NumericFormatSymbol & formatName) override;
+   const NumericFormatSymbol & SSBL_GetBandwidthSelectionFormatName() override;
+   void SSBL_SetBandwidthSelectionFormatName(
+      const NumericFormatSymbol & formatName) override;
+   void SSBL_ModifySpectralSelection(
+      double &bottom, double &top, bool done) override;
+
+private:
+   void OnCloseWindow(wxCloseEvent & event);
+   void OnTimer(wxTimerEvent & event);
+   void OnOpenAudioFile(wxCommandEvent & event);
+   void OnStatusChange( wxCommandEvent& );
+
+   bool SnapSelection();
+
+   // Audio IO callback methods
+   void OnAudioIORate(int rate) override;
+   void OnAudioIOStartRecording() override;
+   void OnAudioIOStopRecording() override;
+   void OnAudioIONewBlockFiles(const AutoSaveFile & blockFileLog) override;
+
+   void InitialState();
+
+   void RestartTimer();
+
    // Declared in this class so that they can have access to private members
    static XMLTagHandler *RecordingRecoveryFactory( AudacityProject &project );
    static ProjectFileIORegistry::Entry sRecoveryFactory;
    static XMLTagHandler *ImportHandlerFactory( AudacityProject &project );
    static ProjectFileIORegistry::Entry sImportHandlerFactory;
 
-public:
-   PlaybackScroller &GetPlaybackScroller() { return *mPlaybackScroller; }
+   // non-static data members
+   AudacityProject &mProject;
+
+   // The handler that handles recovery of <recordingrecovery> tags
+   std::unique_ptr<RecordingRecoveryHandler> mRecordingRecoveryHandler;
+
+   std::unique_ptr<ImportXMLTagHandler> mImportXMLTagHandler;
+
+   std::unique_ptr<wxTimer> mTimer;
+
+   bool mDirty{ false };
+
+   // See explanation in OnCloseWindow
+   bool mIsBeingDeleted{ false };
+
+   // Are we currently closing as the result of a menu command?
+   bool mMenuClose{ false };
+
+   //flag for cancellation of timer record.
+   bool mTimerRecordCanceled{ false };
 
    DECLARE_EVENT_TABLE()
 };
diff --git a/src/TimerRecordDialog.cpp b/src/TimerRecordDialog.cpp
index 9adeed5a3..ec4ef1f88 100644
--- a/src/TimerRecordDialog.cpp
+++ b/src/TimerRecordDialog.cpp
@@ -417,9 +417,10 @@ void TimerRecordDialog::OnOK(wxCommandEvent& WXUNUSED(event))
    // as its possible that they plan to free up some
    // space before the recording begins
    AudacityProject* pProject = GetActiveProject();
+   auto &projectManager = ProjectManager::Get( *pProject );
 
    // How many minutes do we have left on the disc?
-   int iMinsLeft = pProject->GetEstimatedRecordingMinsLeftOnDisk();
+   int iMinsLeft = projectManager.GetEstimatedRecordingMinsLeftOnDisk();
 
    // How many minutes will this recording require?
    int iMinsRecording = m_TimeSpan_Duration.GetMinutes();
@@ -429,9 +430,9 @@ void TimerRecordDialog::OnOK(wxCommandEvent& WXUNUSED(event))
 
       // Format the strings
       wxString sRemainingTime;
-      sRemainingTime = pProject->GetHoursMinsString(iMinsLeft);
+      sRemainingTime = projectManager.GetHoursMinsString(iMinsLeft);
       wxString sPlannedTime;
-      sPlannedTime = pProject->GetHoursMinsString(iMinsRecording);
+      sPlannedTime = projectManager.GetHoursMinsString(iMinsRecording);
 
       // Create the message string
       wxString sMessage;
diff --git a/src/TrackPanel.cpp b/src/TrackPanel.cpp
index f250c0f7c..8798a2db0 100644
--- a/src/TrackPanel.cpp
+++ b/src/TrackPanel.cpp
@@ -610,7 +610,7 @@ void TrackPanel::OnPaint(wxPaintEvent & /* event */)
 
 void TrackPanel::MakeParentModifyState(bool bWantsAutoSave)
 {
-   GetProject()->ModifyState(bWantsAutoSave);
+   ProjectManager::Get( *GetProject() ).ModifyState(bWantsAutoSave);
 }
 
 void TrackPanel::MakeParentRedrawScrollbars()
diff --git a/src/TrackPanelResizeHandle.cpp b/src/TrackPanelResizeHandle.cpp
index 9485bb650..68d98cbd2 100644
--- a/src/TrackPanelResizeHandle.cpp
+++ b/src/TrackPanelResizeHandle.cpp
@@ -219,7 +219,7 @@ UIHandle::Result TrackPanelResizeHandle::Release
    ///  We also modify the undo state (the action doesn't become
    ///  undo-able, but it gets merged with the previous undo-able
    ///  event).
-   pProject->ModifyState(false);
+   ProjectManager::Get( *pProject ).ModifyState(false);
    return RefreshCode::FixScrollbars;
 }
 
diff --git a/src/commands/ImportExportCommands.cpp b/src/commands/ImportExportCommands.cpp
index 736e9de9f..0dcf4585d 100644
--- a/src/commands/ImportExportCommands.cpp
+++ b/src/commands/ImportExportCommands.cpp
@@ -41,7 +41,7 @@ void ImportCommand::PopulateOrExchange(ShuttleGui & S)
 }
 
 bool ImportCommand::Apply(const CommandContext & context){
-   return context.project.Import(mFileName);
+   return ProjectManager::Get( context.project ).Import(mFileName);
 }
 
 
diff --git a/src/commands/OpenSaveCommands.cpp b/src/commands/OpenSaveCommands.cpp
index beebd54e1..e033f52e8 100644
--- a/src/commands/OpenSaveCommands.cpp
+++ b/src/commands/OpenSaveCommands.cpp
@@ -48,11 +48,12 @@ bool OpenProjectCommand::Apply(const CommandContext & context){
    if(mFileName.empty())
    {
       auto project = &context.project;
-      AudacityProject::OpenFiles(project);
+      ProjectManager::OpenFiles(project);
    }
    else
    {
-      context.project.OpenFile(mFileName, mbAddToHistory);
+      ProjectManager::Get( context.project )
+         .OpenFile(mFileName, mbAddToHistory);
    }
    const auto &newFileName = context.project.GetFileName();
 
diff --git a/src/commands/SelectCommand.cpp b/src/commands/SelectCommand.cpp
index b5860adfc..2d82a4dc8 100644
--- a/src/commands/SelectCommand.cpp
+++ b/src/commands/SelectCommand.cpp
@@ -165,7 +165,7 @@ bool SelectFrequenciesCommand::Apply(const CommandContext & context){
    if( !bHasBottom )
       mBottom = 0.0;
 
-   context.project.SSBL_ModifySpectralSelection(
+   ProjectManager::Get( context.project ).SSBL_ModifySpectralSelection(
       mBottom, mTop, false);// false for not done.
    return true;
 }
diff --git a/src/effects/EffectRack.cpp b/src/effects/EffectRack.cpp
index 7031fadec..92cf6a24b 100644
--- a/src/effects/EffectRack.cpp
+++ b/src/effects/EffectRack.cpp
@@ -297,7 +297,7 @@ void EffectRack::OnApply(wxCommandEvent & WXUNUSED(evt))
    auto state = UndoManager::Get( *project ).GetCurrentState();
    auto cleanup = finally( [&] {
       if(!success)
-         project->SetStateTo(state);
+         ProjectManager::Get( *project ).SetStateTo( state );
    } );
 
    for (size_t i = 0, cnt = mEffects.size(); i < cnt; i++)
diff --git a/src/import/ImportLOF.cpp b/src/import/ImportLOF.cpp
index ba6f41990..3895bb87d 100644
--- a/src/import/ImportLOF.cpp
+++ b/src/import/ImportLOF.cpp
@@ -385,7 +385,7 @@ void LOFImportFileHandle::lofOpenFiles(wxString* ln)
           * audio file. TODO: Some sort of message here? */
 
 #endif // USE_MIDI
-         mProject = AudacityProject::OpenProject( mProject, targetfile );
+         mProject = ProjectManager::OpenProject( mProject, targetfile );
 
       // Set tok to right after filename
       temptok2.SetString(targettoken);
@@ -440,7 +440,7 @@ void LOFImportFileHandle::lofOpenFiles(wxString* ln)
                }
 
                // Amend the undo transaction made by import
-               mProject->ModifyState(false);
+               ProjectManager::Get( *mProject ).ModifyState(false);
             } // end of converting "offset" argument
             else
             {
@@ -484,7 +484,7 @@ void LOFImportFileHandle::doDurationAndScrollOffset()
 
    if (doSomething)
       // Amend last undo state
-      mProject->ModifyState(false);
+      ProjectManager::Get( *mProject ).ModifyState(false);
 }
 
 LOFImportFileHandle::~LOFImportFileHandle()
diff --git a/src/menus/ClipMenus.cpp b/src/menus/ClipMenus.cpp
index 46e85fcd4..ccb244b73 100644
--- a/src/menus/ClipMenus.cpp
+++ b/src/menus/ClipMenus.cpp
@@ -389,7 +389,7 @@ void DoSelectClipBoundary(AudacityProject &project, bool next)
       else
          selectedRegion.setT0(results[0].time);
 
-      project.ModifyState(false);
+      ProjectManager::Get( project ).ModifyState(false);
       trackPanel.Refresh(false);
 
       wxString message = ClipBoundaryMessage(results);
@@ -572,7 +572,7 @@ void DoSelectClip(AudacityProject &project, bool next)
       double t0 = results[0].startTime;
       double t1 = results[0].endTime;
       selectedRegion.setTimes(t0, t1);
-      project.ModifyState(false);
+      ProjectManager::Get( project ).ModifyState(false);
       trackPanel.ScrollIntoView(selectedRegion.t0());
       trackPanel.Refresh(false);
 
@@ -618,7 +618,7 @@ void DoCursorClipBoundary
       // value.
       double time = results[0].time;
       selectedRegion.setTimes(time, time);
-      project.ModifyState(false);
+      ProjectManager::Get( project ).ModifyState(false);
       trackPanel.ScrollIntoView(selectedRegion.t0());
       trackPanel.Refresh(false);
 
@@ -720,7 +720,8 @@ void DoClipLeftOrRight
       // keypress (keydown, then keyup), and holding down a key
       // (multiple keydowns followed by a keyup) result in a single
       // entry in Audacity's history dialog.
-      project.PushState(message, _("Time-Shift"), UndoPush::CONSOLIDATE);
+      ProjectManager::Get( project )
+         .PushState(message, _("Time-Shift"), UndoPush::CONSOLIDATE);
    }
 
    if ( amount == 0.0 )
diff --git a/src/menus/EditMenus.cpp b/src/menus/EditMenus.cpp
index 043b5620b..90bf5827a 100644
--- a/src/menus/EditMenus.cpp
+++ b/src/menus/EditMenus.cpp
@@ -49,7 +49,8 @@ bool DoPasteText(AudacityProject &project)
          if (pLabelTrack->PasteSelectedText(selectedRegion.t0(),
                                             selectedRegion.t1()))
          {
-            project.PushState(_("Pasted text from the clipboard"), _("Paste"));
+            ProjectManager::Get( project )
+               .PushState(_("Pasted text from the clipboard"), _("Paste"));
 
             // Make sure caret is in view
             int x;
@@ -148,7 +149,8 @@ bool DoPasteNothingSelected(AudacityProject &project)
                 // half a sample earlier
          quantT1 - quantT0);
 
-      project.PushState(_("Pasted from the clipboard"), _("Paste"));
+      ProjectManager::Get( project )
+         .PushState(_("Pasted from the clipboard"), _("Paste"));
 
       window.RedrawProject();
 
@@ -216,7 +218,7 @@ bool DoEditMetadata
       if (tags != *newTags) {
          // Commit the change to project state only now.
          Tags::Set( project, newTags );
-         project.PushState(title, shortUndoDescription);
+         ProjectManager::Get( project ).PushState(title, shortUndoDescription);
       }
       bool bShowInFuture;
       gPrefs->Read(wxT("/AudioFiles/ShowId3Dialog"), &bShowInFuture, true);
@@ -233,7 +235,7 @@ void DoUndo(AudacityProject &project)
    auto &undoManager = UndoManager::Get( project );
    auto &window = ProjectWindow::Get( project );
 
-   if (!project.UndoAvailable()) {
+   if (!ProjectManager::Get( project ).UndoAvailable()) {
       AudacityMessageBox(_("Nothing to undo"));
       return;
    }
@@ -244,7 +246,8 @@ void DoUndo(AudacityProject &project)
    }
 
    undoManager.Undo(
-      [&]( const UndoState &state ){ project.PopState( state ); } );
+      [&]( const UndoState &state ){
+         ProjectManager::Get( project ).PopState( state ); } );
 
    trackPanel.EnsureVisible(trackPanel.GetFirstSelectedTrack());
 
@@ -269,7 +272,7 @@ void OnRedo(const CommandContext &context)
    auto &undoManager = UndoManager::Get( project );
    auto &window = ProjectWindow::Get( project );
 
-   if (!project.RedoAvailable()) {
+   if (!ProjectManager::Get( project ).RedoAvailable()) {
       AudacityMessageBox(_("Nothing to redo"));
       return;
    }
@@ -279,7 +282,8 @@ void OnRedo(const CommandContext &context)
    }
 
    undoManager.Redo(
-      [&]( const UndoState &state ){ project.PopState( state ); } );
+      [&]( const UndoState &state ){
+         ProjectManager::Get( project ).PopState( state ); } );
 
    trackPanel.EnsureVisible(trackPanel.GetFirstSelectedTrack());
 
@@ -366,7 +370,7 @@ void OnCut(const CommandContext &context)
 
    selectedRegion.collapseToT0();
 
-   project.PushState(_("Cut to the clipboard"), _("Cut"));
+   ProjectManager::Get( project ).PushState(_("Cut to the clipboard"), _("Cut"));
 
    // Bug 1663
    //mRuler->ClearPlayRegion();
@@ -392,7 +396,7 @@ void OnDelete(const CommandContext &context)
 
    selectedRegion.collapseToT0();
 
-   project.PushState(wxString::Format(_("Deleted %.2f seconds at t=%.2f"),
+   ProjectManager::Get( project ).PushState(wxString::Format(_("Deleted %.2f seconds at t=%.2f"),
                               seconds,
                               selectedRegion.t0()),
              _("Delete"));
@@ -692,7 +696,8 @@ void OnPaste(const CommandContext &context)
    {
       selectedRegion.setT1( t0 + clipboard.Duration() );
 
-      project.PushState(_("Pasted from the clipboard"), _("Paste"));
+      ProjectManager::Get( project )
+         .PushState(_("Pasted from the clipboard"), _("Paste"));
 
       window.RedrawProject();
 
@@ -724,7 +729,7 @@ void OnDuplicate(const CommandContext &context)
          break;
    }
 
-   project.PushState(_("Duplicated"), _("Duplicate"));
+   ProjectManager::Get( project ).PushState(_("Duplicated"), _("Duplicate"));
 
    window.RedrawProject();
 }
@@ -766,7 +771,7 @@ void OnSplitCut(const CommandContext &context)
    clipboard.Assign( std::move( newClipboard ),
       selectedRegion.t0(), selectedRegion.t1(), &project );
 
-   project.PushState(_("Split-cut to the clipboard"), _("Split Cut"));
+   ProjectManager::Get( project ).PushState(_("Split-cut to the clipboard"), _("Split Cut"));
 
    window.RedrawProject();
 }
@@ -789,7 +794,7 @@ void OnSplitDelete(const CommandContext &context)
       }
    );
 
-   project.PushState(
+   ProjectManager::Get( project ).PushState(
       wxString::Format(_("Split-deleted %.2f seconds at t=%.2f"),
          selectedRegion.duration(),
          selectedRegion.t0()),
@@ -808,7 +813,7 @@ void OnSilence(const CommandContext &context)
    for ( auto n : tracks.Selected< AudioTrack >() )
       n->Silence(selectedRegion.t0(), selectedRegion.t1());
 
-   project.PushState(
+   ProjectManager::Get( project ).PushState(
       wxString::Format(_("Silenced selected tracks for %.2f seconds at %.2f"),
          selectedRegion.duration(),
          selectedRegion.t0()),
@@ -841,7 +846,7 @@ void OnTrim(const CommandContext &context)
       }
    );
 
-   project.PushState(
+   ProjectManager::Get( project ).PushState(
       wxString::Format(
          _("Trim selected audio tracks from %.2f seconds to %.2f seconds"),
          selectedRegion.t0(), selectedRegion.t1()),
@@ -863,7 +868,7 @@ void OnSplit(const CommandContext &context)
    for (auto wt : tracks.Selected< WaveTrack >())
       wt->Split( sel0, sel1 );
 
-   project.PushState(_("Split"), _("Split"));
+   ProjectManager::Get( project ).PushState(_("Split"), _("Split"));
    trackPanel.Refresh(false);
 #if 0
 //ANSWER-ME: Do we need to keep this commented out OnSplit() code?
@@ -963,7 +968,8 @@ void OnSplitNew(const CommandContext &context)
          break;
    }
 
-   project.PushState(_("Split to new track"), _("Split New"));
+   ProjectManager::Get( project )
+      .PushState(_("Split to new track"), _("Split New"));
 
    window.RedrawProject();
 }
@@ -979,7 +985,7 @@ void OnJoin(const CommandContext &context)
       wt->Join(selectedRegion.t0(),
                selectedRegion.t1());
 
-   project.PushState(
+   ProjectManager::Get( project ).PushState(
       wxString::Format(_("Joined %.2f seconds at t=%.2f"),
          selectedRegion.duration(),
          selectedRegion.t0()),
@@ -999,7 +1005,7 @@ void OnDisjoin(const CommandContext &context)
       wt->Disjoin(selectedRegion.t0(),
                   selectedRegion.t1());
 
-   project.PushState(
+   ProjectManager::Get( project ).PushState(
       wxString::Format(_("Detached %.2f seconds at t=%.2f"),
          selectedRegion.duration(),
          selectedRegion.t0()),
diff --git a/src/menus/FileMenus.cpp b/src/menus/FileMenus.cpp
index 7cba59f65..3940b4169 100644
--- a/src/menus/FileMenus.cpp
+++ b/src/menus/FileMenus.cpp
@@ -116,7 +116,7 @@ AudacityProject *DoImportMIDI(
 
    AudacityProject *pNewProject {};
    if ( !pProject )
-      pProject = pNewProject = CreateNewAudacityProject();
+      pProject = pNewProject = ProjectManager::New();
    auto cleanup = finally( [&]
       { if ( pNewProject ) GetProjectFrame( *pNewProject ).Close(true); } );
 
@@ -128,7 +128,8 @@ AudacityProject *DoImportMIDI(
       auto pTrack = tracks.Add( newTrack );
       pTrack->SetSelected(true);
 
-      pProject->PushState(wxString::Format(_("Imported MIDI from '%s'"),
+      ProjectManager::Get( *pProject )
+         .PushState(wxString::Format(_("Imported MIDI from '%s'"),
          fileName), _("Import MIDI"));
 
       ProjectWindow::Get( *pProject ).ZoomAfterImport(pTrack);
@@ -151,13 +152,13 @@ struct Handler : CommandHandlerObject {
 
 void OnNew(const CommandContext & )
 {
-   CreateNewAudacityProject();
+   ( void ) ProjectManager::New();
 }
 
 void OnOpen(const CommandContext &context )
 {
    auto &project = context.project;
-   AudacityProject::OpenFiles(&project);
+   ProjectManager::OpenFiles(&project);
 }
 
 // JKC: This is like OnClose, except it emptys the project in place,
@@ -168,14 +169,14 @@ void OnOpen(const CommandContext &context )
 void OnProjectReset(const CommandContext &context)
 {
    auto &project = context.project;
-   project.ResetProjectToEmpty();
+   ProjectManager::Get( project ).ResetProjectToEmpty();
 }
 
 void OnClose(const CommandContext &context )
 {
    auto &project = context.project;
-   auto &window = GetProjectFrame( project );
-   project.SetMenuClose(true);
+   auto &window = ProjectWindow::Get( project );
+   ProjectManager::Get( project ).SetMenuClose(true);
    window.Close();
 }
 
@@ -405,7 +406,7 @@ void OnImport(const CommandContext &context)
    // this serves to track the file if the users zooms in and such.
    MissingAliasFilesDialog::SetShouldShow(true);
 
-   wxArrayString selectedFiles = project.ShowOpenDialog(wxT(""));
+   wxArrayString selectedFiles = ProjectManager::ShowOpenDialog(wxT(""));
    if (selectedFiles.size() == 0) {
       gPrefs->Write(wxT("/LastOpenType"),wxT(""));
       gPrefs->Flush();
@@ -435,7 +436,7 @@ void OnImport(const CommandContext &context)
 
       FileNames::UpdateDefaultPath(FileNames::Operation::Open, fileName);
 
-      project.Import(fileName);
+      ProjectManager::Get( project ).Import(fileName);
    }
 
    window.ZoomAfterImport(nullptr);
@@ -479,9 +480,9 @@ void OnImportLabels(const CommandContext &context)
       newTrack->SetSelected(true);
       tracks.Add( newTrack );
 
-      project.PushState(wxString::
-                Format(_("Imported labels from '%s'"), fileName),
-                _("Import Labels"));
+      ProjectManager::Get( project ).PushState(
+         wxString::Format(_("Imported labels from '%s'"), fileName),
+            _("Import Labels"));
 
       window.ZoomAfterImport(nullptr);
    }
@@ -532,7 +533,7 @@ void OnImportRaw(const CommandContext &context)
    if (newTracks.size() <= 0)
       return;
 
-   project.AddImportedTracks(fileName, std::move(newTracks));
+   ProjectManager::Get( project ).AddImportedTracks(fileName, std::move(newTracks));
    window.HandleResize(); // Adjust scrollers for NEW track sizes.
 }
 
diff --git a/src/menus/HelpMenus.cpp b/src/menus/HelpMenus.cpp
index b25698f9e..4ad83ab39 100644
--- a/src/menus/HelpMenus.cpp
+++ b/src/menus/HelpMenus.cpp
@@ -251,7 +251,7 @@ void QuickFixDialog::OnFix(wxCommandEvent &event)
       // preference dialogs.
       if( Str == "/SnapTo" )
       {
-         pProject->AS_SetSnapTo( 0 );
+         ProjectManager::Get( *pProject ).AS_SetSnapTo( 0 );
       }
       else
       {
diff --git a/src/menus/LabelMenus.cpp b/src/menus/LabelMenus.cpp
index 0dd22865d..aed8c9b47 100644
--- a/src/menus/LabelMenus.cpp
+++ b/src/menus/LabelMenus.cpp
@@ -71,7 +71,7 @@ int DoAddLabel(
 
    int index = lt->AddLabel(region, title, focusTrackNumber);
 
-   project.PushState(_("Added label"), _("Label"));
+   ProjectManager::Get( project ).PushState(_("Added label"), _("Label"));
 
    window.RedrawProject();
    if (!useDialog) {
@@ -336,7 +336,7 @@ void OnPasteNewLabel(const CommandContext &context)
    }
 
    if (bPastedSomething) {
-      project.PushState(
+      ProjectManager::Get( project ).PushState(
          _("Pasted from the clipboard"), _("Paste Text to New Label"));
 
       // Is this necessary? (carried over from former logic in OnPaste())
@@ -376,7 +376,7 @@ void OnCutLabels(const CommandContext &context)
 
    selectedRegion.collapseToT0();
 
-   project.PushState(
+   ProjectManager::Get( project ).PushState(
    /* i18n-hint: (verb) past tense.  Audacity has just cut the labeled audio
       regions.*/
       _( "Cut labeled audio regions to clipboard" ),
@@ -400,7 +400,7 @@ void OnDeleteLabels(const CommandContext &context)
 
    selectedRegion.collapseToT0();
 
-   project.PushState(
+   ProjectManager::Get( project ).PushState(
       /* i18n-hint: (verb) Audacity has just deleted the labeled audio regions*/
       _( "Deleted labeled audio regions" ),
       /* i18n-hint: (verb)*/
@@ -422,7 +422,7 @@ void OnSplitCutLabels(const CommandContext &context)
    EditClipboardByLabel( project,
       tracks, selectedRegion, &WaveTrack::SplitCut );
 
-   project.PushState(
+   ProjectManager::Get( project ).PushState(
       /* i18n-hint: (verb) Audacity has just split cut the labeled audio
          regions*/
       _( "Split Cut labeled audio regions to clipboard" ),
@@ -444,7 +444,7 @@ void OnSplitDeleteLabels(const CommandContext &context)
 
    EditByLabel( tracks, selectedRegion, &WaveTrack::SplitDelete, false );
 
-   project.PushState(
+   ProjectManager::Get( project ).PushState(
       /* i18n-hint: (verb) Audacity has just done a special kind of DELETE on
          the labeled audio regions */
       _( "Split Deleted labeled audio regions" ),
@@ -467,7 +467,7 @@ void OnSilenceLabels(const CommandContext &context)
 
    EditByLabel( tracks, selectedRegion, &WaveTrack::Silence, false );
 
-   project.PushState(
+   ProjectManager::Get( project ).PushState(
       /* i18n-hint: (verb)*/
       _( "Silenced labeled audio regions" ),
       /* i18n-hint: (verb)*/
@@ -489,7 +489,7 @@ void OnCopyLabels(const CommandContext &context)
    EditClipboardByLabel( project,
       tracks, selectedRegion, &WaveTrack::CopyNonconst );
 
-   project.PushState( _( "Copied labeled audio regions to clipboard" ),
+   ProjectManager::Get( project ).PushState( _( "Copied labeled audio regions to clipboard" ),
    /* i18n-hint: (verb)*/
       _( "Copy Labeled Audio" ) );
 
@@ -505,7 +505,7 @@ void OnSplitLabels(const CommandContext &context)
 
    EditByLabel( tracks, selectedRegion, &WaveTrack::Split, false );
 
-   project.PushState(
+   ProjectManager::Get( project ).PushState(
       /* i18n-hint: (verb) past tense.  Audacity has just split the labeled
          audio (a point or a region)*/
       _( "Split labeled audio (points or regions)" ),
@@ -527,7 +527,7 @@ void OnJoinLabels(const CommandContext &context)
 
    EditByLabel( tracks, selectedRegion, &WaveTrack::Join, false );
 
-   project.PushState(
+   ProjectManager::Get( project ).PushState(
       /* i18n-hint: (verb) Audacity has just joined the labeled audio (points or
          regions) */
       _( "Joined labeled audio (points or regions)" ),
@@ -549,7 +549,7 @@ void OnDisjoinLabels(const CommandContext &context)
 
    EditByLabel( tracks, selectedRegion, &WaveTrack::Disjoin, false );
 
-   project.PushState(
+   ProjectManager::Get( project ).PushState(
       /* i18n-hint: (verb) Audacity has just detached the labeled audio regions.
       This message appears in history and tells you about something
       Audacity has done.*/
diff --git a/src/menus/NavigationMenus.cpp b/src/menus/NavigationMenus.cpp
index c1eaa41f9..ce6db3776 100644
--- a/src/menus/NavigationMenus.cpp
+++ b/src/menus/NavigationMenus.cpp
@@ -84,6 +84,7 @@ void NextOrPrevFrame(AudacityProject &project, bool forward)
 void DoPrevTrack(
    AudacityProject &project, bool shift, bool circularTrackNavigation )
 {
+   auto &projectManager = ProjectManager::Get( project );
    auto &trackPanel = TrackPanel::Get( project );
    auto &tracks = TrackList::Get( project );
    auto &selectionState = SelectionState::Get( project );
@@ -94,7 +95,7 @@ void DoPrevTrack(
       t = *tracks.Any().rbegin();
       trackPanel.SetFocusedTrack( t );
       trackPanel.EnsureVisible( t );
-      project.ModifyState(false);
+      projectManager.ModifyState(false);
       return;
    }
 
@@ -126,7 +127,7 @@ void DoPrevTrack(
             ( *t, false, false );
          trackPanel.SetFocusedTrack( p );   // move focus to next track up
          trackPanel.EnsureVisible( p );
-         project.ModifyState(false);
+         projectManager.ModifyState(false);
          return;
       }
       if( tSelected && !pSelected )
@@ -135,7 +136,7 @@ void DoPrevTrack(
             ( *p, true, false );
          trackPanel.SetFocusedTrack( p );   // move focus to next track up
          trackPanel.EnsureVisible( p );
-         project.ModifyState(false);
+         projectManager.ModifyState(false);
          return;
       }
       if( !tSelected && pSelected )
@@ -144,7 +145,7 @@ void DoPrevTrack(
             ( *p, false, false );
          trackPanel.SetFocusedTrack( p );   // move focus to next track up
          trackPanel.EnsureVisible( p );
-         project.ModifyState(false);
+         projectManager.ModifyState(false);
          return;
       }
       if( !tSelected && !pSelected )
@@ -153,7 +154,7 @@ void DoPrevTrack(
             ( *t, true, false );
          trackPanel.SetFocusedTrack( p );   // move focus to next track up
          trackPanel.EnsureVisible( p );
-          project.ModifyState(false);
+          projectManager.ModifyState(false);
          return;
       }
    }
@@ -169,7 +170,7 @@ void DoPrevTrack(
             p = * range.rbegin(); // null if range is empty
             trackPanel.SetFocusedTrack( p );   // Wrap to the last track
             trackPanel.EnsureVisible( p );
-             project.ModifyState(false);
+             projectManager.ModifyState(false);
             return;
          }
          else
@@ -182,7 +183,7 @@ void DoPrevTrack(
       {
          trackPanel.SetFocusedTrack( p );   // move focus to next track up
          trackPanel.EnsureVisible( p );
-         project.ModifyState(false);
+         projectManager.ModifyState(false);
          return;
       }
    }
@@ -194,6 +195,7 @@ void DoPrevTrack(
 void DoNextTrack(
    AudacityProject &project, bool shift, bool circularTrackNavigation )
 {
+   auto &projectManager = ProjectManager::Get( project );
    auto &trackPanel = TrackPanel::Get( project );
    auto &tracks = TrackList::Get( project );
    auto &selectionState = SelectionState::Get( project );
@@ -204,7 +206,7 @@ void DoNextTrack(
       t = *tracks.Any().begin();
       trackPanel.SetFocusedTrack( t );
       trackPanel.EnsureVisible( t );
-      project.ModifyState(false);
+      projectManager.ModifyState(false);
       return;
    }
 
@@ -230,7 +232,7 @@ void DoNextTrack(
             ( *t, false, false );
          trackPanel.SetFocusedTrack( n );   // move focus to next track down
          trackPanel.EnsureVisible( n );
-         project.ModifyState(false);
+         projectManager.ModifyState(false);
          return;
       }
       if( tSelected && !nSelected )
@@ -239,7 +241,7 @@ void DoNextTrack(
             ( *n, true, false );
          trackPanel.SetFocusedTrack( n );   // move focus to next track down
          trackPanel.EnsureVisible( n );
-         project.ModifyState(false);
+         projectManager.ModifyState(false);
          return;
       }
       if( !tSelected && nSelected )
@@ -248,7 +250,7 @@ void DoNextTrack(
             ( *n, false, false );
          trackPanel.SetFocusedTrack( n );   // move focus to next track down
          trackPanel.EnsureVisible( n );
-         project.ModifyState(false);
+         projectManager.ModifyState(false);
          return;
       }
       if( !tSelected && !nSelected )
@@ -257,7 +259,7 @@ void DoNextTrack(
             ( *t, true, false );
          trackPanel.SetFocusedTrack( n );   // move focus to next track down
          trackPanel.EnsureVisible( n );
-         project.ModifyState(false);
+         projectManager.ModifyState(false);
          return;
       }
    }
@@ -272,7 +274,7 @@ void DoNextTrack(
             n = *tracks.Any().begin();
             trackPanel.SetFocusedTrack( n );   // Wrap to the first track
             trackPanel.EnsureVisible( n );
-            project.ModifyState(false);
+            projectManager.ModifyState(false);
             return;
          }
          else
@@ -285,7 +287,7 @@ void DoNextTrack(
       {
          trackPanel.SetFocusedTrack( n );   // move focus to next track down
          trackPanel.EnsureVisible( n );
-         project.ModifyState(false);
+         projectManager.ModifyState(false);
          return;
       }
    }
@@ -470,7 +472,7 @@ void OnFirstTrack(const CommandContext &context)
    if (t != f)
    {
       trackPanel.SetFocusedTrack(f);
-      project.ModifyState(false);
+      ProjectManager::Get( project ).ModifyState(false);
    }
    trackPanel.EnsureVisible(f);
 }
@@ -489,7 +491,7 @@ void OnLastTrack(const CommandContext &context)
    if (t != l)
    {
       trackPanel.SetFocusedTrack(l);
-      project.ModifyState(false);
+      ProjectManager::Get( project ).ModifyState(false);
    }
    trackPanel.EnsureVisible(l);
 }
@@ -521,7 +523,7 @@ void OnToggle(const CommandContext &context)
    selectionState.SelectTrack
       ( *t, !t->GetSelected(), true );
    trackPanel.EnsureVisible( t );
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
 
    trackPanel.GetAx().Updated();
 
diff --git a/src/menus/PluginMenus.cpp b/src/menus/PluginMenus.cpp
index b04f1116f..f056d6678 100644
--- a/src/menus/PluginMenus.cpp
+++ b/src/menus/PluginMenus.cpp
@@ -493,7 +493,7 @@ bool DoEffect(
    {
       wxString shortDesc = em.GetCommandName(ID);
       wxString longDesc = em.GetCommandDescription(ID);
-      project.PushState(longDesc, shortDesc);
+      ProjectManager::Get( project ).PushState(longDesc, shortDesc);
    }
 
    if (!(flags & kDontRepeatLast))
diff --git a/src/menus/SelectMenus.cpp b/src/menus/SelectMenus.cpp
index d2c978253..3022ed2dc 100644
--- a/src/menus/SelectMenus.cpp
+++ b/src/menus/SelectMenus.cpp
@@ -38,7 +38,7 @@ void DoSelectTimeAndTracks
       for (auto t : tracks.Any())
          t->SetSelected(true);
 
-      project.ModifyState(false);
+      ProjectManager::Get( project ).ModifyState(false);
       trackPanel.Refresh(false);
    }
 }
@@ -63,7 +63,7 @@ void DoSelectTimeAndAudioTracks
       for (auto t : tracks.Any<WaveTrack>())
          t->SetSelected(true);
 
-      project.ModifyState(false);
+      ProjectManager::Get( project ).ModifyState(false);
       trackPanel.Refresh(false);
    }
 }
@@ -88,7 +88,7 @@ void DoNextPeakFrequency(AudacityProject &project, bool up)
       SpectrumAnalyst analyst;
       SelectHandle::SnapCenterOnce(analyst, viewInfo, pTrack, up);
       trackPanel.Refresh(false);
-      project.ModifyState(false);
+      ProjectManager::Get( project ).ModifyState(false);
    }
 }
 
@@ -179,7 +179,7 @@ bool OnlyHandleKeyUp( const CommandContext &context )
    if( !bKeyUp )
       return false;
 
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
    return true;
 }
 
@@ -420,7 +420,7 @@ void DoCursorMove(
       MoveWhenAudioInactive(project, seekStep, TIME_UNIT_SECONDS);
    }
 
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
 }
 
 void DoBoundaryMove(AudacityProject &project, int step, SeekInfo &info)
@@ -454,7 +454,7 @@ void DoBoundaryMove(AudacityProject &project, int step, SeekInfo &info)
       else
          viewInfo.selectedRegion.setT1(indicator);
 
-      project.ModifyState(false);
+      ProjectManager::Get( project ).ModifyState(false);
       trackPanel.Refresh(false);
       return;
    }
@@ -483,7 +483,7 @@ void DoBoundaryMove(AudacityProject &project, int step, SeekInfo &info)
    trackPanel.ScrollIntoView(newT);
    trackPanel.Refresh(false);
 
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
 }
 
 }
@@ -533,7 +533,7 @@ void DoListSelection
       trackPanel.SetFocusedTrack(t);
    window.Refresh(false);
    if (modifyState)
-      project.ModifyState(true);
+      ProjectManager::Get( project ).ModifyState(true);
 }
 
 void DoSelectAll(AudacityProject &project)
@@ -583,7 +583,7 @@ void OnSelectNone(const CommandContext &context)
 
    selectedRegion.collapseToT0();
    SelectNone( project );
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
 }
 
 void OnSelectAllTracks(const CommandContext &context)
@@ -606,7 +606,7 @@ void OnSelectSyncLockSel(const CommandContext &context)
    }
 
    if (selected)
-      project.ModifyState(false);
+      ProjectManager::Get( project ).ModifyState(false);
 
    trackPanel.Refresh(false);
 }
@@ -649,7 +649,7 @@ void OnSetLeftSelection(const CommandContext &context)
 
    if (bSelChanged)
    {
-      project.ModifyState(false);
+      ProjectManager::Get( project ).ModifyState(false);
       trackPanel.Refresh(false);
    }
 }
@@ -689,7 +689,7 @@ void OnSetRightSelection(const CommandContext &context)
 
    if (bSelChanged)
    {
-      project.ModifyState(false);
+      ProjectManager::Get( project ).ModifyState(false);
       trackPanel.Refresh(false);
    }
 }
@@ -715,7 +715,7 @@ void OnSelectStartCursor(const CommandContext &context)
 
    selectedRegion.setT0(minOffset);
 
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
 
    trackPanel.Refresh(false);
 }
@@ -741,7 +741,7 @@ void OnSelectCursorEnd(const CommandContext &context)
 
    selectedRegion.setT1(maxEndOffset);
 
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
 
    trackPanel.Refresh(false);
 }
@@ -761,7 +761,7 @@ void OnSelectTrackStartToEnd(const CommandContext &context)
       return;
 
    viewInfo.selectedRegion.setTimes( minOffset, maxEndOffset );
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
 
    trackPanel.Refresh(false);
 }
@@ -789,7 +789,7 @@ void OnSelectionRestore(const CommandContext &context)
 
    selectedRegion = mRegionSave;
 
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
 
    trackPanel.Refresh(false);
 }
@@ -822,7 +822,7 @@ void OnToggleSpectralSelection(const CommandContext &context)
       selectedRegion.setFrequencies(mLastF0, mLastF1);
 
    trackPanel.Refresh(false);
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
 }
 
 void OnNextHigherPeakFrequency(const CommandContext &context)
@@ -857,7 +857,7 @@ void OnSelectCursorStoredCursor(const CommandContext &context)
          std::min(cursorPositionCurrent, mCursorPositionStored),
          std::max(cursorPositionCurrent, mCursorPositionStored));
 
-      project.ModifyState(false);
+      ProjectManager::Get( project ).ModifyState(false);
       trackPanel.Refresh(false);
    }
 }
@@ -890,7 +890,7 @@ void OnZeroCrossing(const CommandContext &context)
          selectedRegion.setTimes(t0, t1);
    }
 
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
 
    trackPanel.Refresh(false);
 }
@@ -898,19 +898,19 @@ void OnZeroCrossing(const CommandContext &context)
 void OnSnapToOff(const CommandContext &context)
 {
    auto &project = context.project;
-   project.AS_SetSnapTo(SNAP_OFF);
+   ProjectManager::Get( project ).AS_SetSnapTo(SNAP_OFF);
 }
 
 void OnSnapToNearest(const CommandContext &context)
 {
    auto &project = context.project;
-   project.AS_SetSnapTo(SNAP_NEAREST);
+   ProjectManager::Get( project ).AS_SetSnapTo(SNAP_NEAREST);
 }
 
 void OnSnapToPrior(const CommandContext &context)
 {
    auto &project = context.project;
-   project.AS_SetSnapTo(SNAP_PRIOR);
+   ProjectManager::Get( project ).AS_SetSnapTo(SNAP_PRIOR);
 }
 
 void OnSelToStart(const CommandContext &context)
@@ -918,7 +918,7 @@ void OnSelToStart(const CommandContext &context)
    auto &project = context.project;
    auto &window = ProjectWindow::Get( project );
    window.Rewind(true);
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
 }
 
 void OnSelToEnd(const CommandContext &context)
@@ -926,7 +926,7 @@ void OnSelToEnd(const CommandContext &context)
    auto &project = context.project;
    auto &window = ProjectWindow::Get( project );
    window.SkipEnd(true);
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
 }
 
 // Handler state:
@@ -977,7 +977,7 @@ void OnCursorSelStart(const CommandContext &context)
    auto &selectedRegion = ViewInfo::Get( project ).selectedRegion;
 
    selectedRegion.collapseToT0();
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
    trackPanel.ScrollIntoView(selectedRegion.t0());
    trackPanel.Refresh(false);
 }
@@ -989,7 +989,7 @@ void OnCursorSelEnd(const CommandContext &context)
    auto &selectedRegion = ViewInfo::Get( project ).selectedRegion;
 
    selectedRegion.collapseToT1();
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
    trackPanel.ScrollIntoView(selectedRegion.t1());
    trackPanel.Refresh(false);
 }
@@ -1016,7 +1016,7 @@ void OnCursorTrackStart(const CommandContext &context)
       return;
 
    selectedRegion.setTimes(minOffset, minOffset);
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
    trackPanel.ScrollIntoView(selectedRegion.t0());
    trackPanel.Refresh(false);
 }
@@ -1043,7 +1043,7 @@ void OnCursorTrackEnd(const CommandContext &context)
       return;
 
    selectedRegion.setTimes(maxEndOffset, maxEndOffset);
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
    trackPanel.ScrollIntoView(selectedRegion.t1());
    trackPanel.Refresh(false);
 }
@@ -1055,7 +1055,7 @@ void OnSkipStart(const CommandContext &context)
 
    auto &controlToolBar = ControlToolBar::Get( project );
    controlToolBar.OnRewind(evt);
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
 }
 
 void OnSkipEnd(const CommandContext &context)
@@ -1065,7 +1065,7 @@ void OnSkipEnd(const CommandContext &context)
 
    auto &controlToolBar = ControlToolBar::Get( project );
    controlToolBar.OnFF(evt);
-   project.ModifyState(false);
+   ProjectManager::Get( project ).ModifyState(false);
 }
 
 void OnCursorLeft(const CommandContext &context)
diff --git a/src/menus/TrackMenus.cpp b/src/menus/TrackMenus.cpp
index e2c782725..5e0f3257b 100644
--- a/src/menus/TrackMenus.cpp
+++ b/src/menus/TrackMenus.cpp
@@ -91,7 +91,7 @@ void DoMixAndRender
          msg.Printf(_("Rendered all audio in track '%s'"), firstName);
          /* i18n-hint: Convert the audio into a more usable form, so apply
           * panning and amplification and write to some external file.*/
-         project.PushState(msg, _("Render"));
+         ProjectManager::Get( project ).PushState(msg, _("Render"));
       }
       else {
          wxString msg;
@@ -103,7 +103,7 @@ void DoMixAndRender
             msg.Printf(
                _("Mixed and rendered %d tracks into one new mono track"),
                (int)selectedCount);
-         project.PushState(msg, _("Mix and Render"));
+         ProjectManager::Get( project ).PushState(msg, _("Mix and Render"));
       }
 
       trackPanel.SetFocus();
@@ -131,7 +131,8 @@ void DoPanTracks(AudacityProject &project, float PanValue)
 
    auto flags = UndoPush::AUTOSAVE;
    /*i18n-hint: One or more audio tracks have been panned*/
-   project.PushState(_("Panned audio track(s)"), _("Pan Track"), flags);
+   ProjectManager::Get( project )
+      .PushState(_("Panned audio track(s)"), _("Pan Track"), flags);
          flags = flags | UndoPush::CONSOLIDATE;
 }
 
@@ -292,7 +293,7 @@ void DoAlign
    if (moveSel)
       selectedRegion.move(delta);
 
-   project.PushState(action, shortAction);
+   ProjectManager::Get( project ).PushState(action, shortAction);
 
    window.RedrawProject();
 }
@@ -537,7 +538,8 @@ void SetTrackGain(AudacityProject &project, WaveTrack * wt, LWSlider * slider)
    for (auto channel : TrackList::Channels(wt))
       channel->SetGain(newValue);
 
-   project.PushState(_("Adjusted gain"), _("Gain"), UndoPush::CONSOLIDATE);
+   ProjectManager::Get( project )
+      .PushState(_("Adjusted gain"), _("Gain"), UndoPush::CONSOLIDATE);
 
    TrackPanel::Get( project ).RefreshTrack(wt);
 }
@@ -550,7 +552,8 @@ void SetTrackPan(AudacityProject &project, WaveTrack * wt, LWSlider * slider)
    for (auto channel : TrackList::Channels(wt))
       channel->SetPan(newValue);
 
-   project.PushState(_("Adjusted Pan"), _("Pan"), UndoPush::CONSOLIDATE);
+   ProjectManager::Get( project )
+      .PushState(_("Adjusted Pan"), _("Pan"), UndoPush::CONSOLIDATE);
 
    TrackPanel::Get( project ).RefreshTrack(wt);
 }
@@ -595,7 +598,8 @@ void DoRemoveTracks( AudacityProject &project )
    if (f)
       trackPanel.EnsureVisible(f);
 
-   project.PushState(_("Removed audio track(s)"), _("Remove Track"));
+   ProjectManager::Get( project )
+      .PushState(_("Removed audio track(s)"), _("Remove Track"));
 
    trackPanel.UpdateViewIfNoTracks();
    trackPanel.Refresh(false);
@@ -645,7 +649,7 @@ void DoTrackMute(AudacityProject &project, Track *t, bool exclusive)
             track->SetSolo( (nPlaying==1) && (nPlayableTracks > 1 ) && !track->GetMute() );
       }
    }
-   project.ModifyState(true);
+   ProjectManager::Get( project ).ModifyState(true);
 
    trackPanel.UpdateAccessibility();
    trackPanel.Refresh(false);
@@ -698,7 +702,7 @@ void DoTrackSolo(AudacityProject &project, Track *t, bool exclusive)
          }
       }
    }
-   project.ModifyState(true);
+   ProjectManager::Get( project ).ModifyState(true);
 
    trackPanel.UpdateAccessibility();
    trackPanel.Refresh(false);
@@ -734,7 +738,7 @@ void DoRemoveTrack(AudacityProject &project, Track * toRemove)
    if (toRemoveWasFocused)
       trackPanel.SetFocusedTrack(newFocus);
 
-   project.PushState(
+   ProjectManager::Get( project ).PushState(
       wxString::Format(_("Removed track '%s.'"),
       name),
       _("Track Remove"));
@@ -793,7 +797,7 @@ void DoMoveTrack
 
    longDesc = longDesc.Format(target->GetName());
 
-   project.PushState(longDesc, shortDesc);
+   ProjectManager::Get( project ).PushState(longDesc, shortDesc);
    trackPanel.Refresh(false);
 }
 
@@ -818,7 +822,8 @@ void OnNewWaveTrack(const CommandContext &context)
 
    t->SetSelected(true);
 
-   project.PushState(_("Created new audio track"), _("New Track"));
+   ProjectManager::Get( project )
+      .PushState(_("Created new audio track"), _("New Track"));
 
    window.RedrawProject();
    trackPanel.EnsureVisible(t);
@@ -846,7 +851,8 @@ void OnNewStereoTrack(const CommandContext &context)
 
    tracks.GroupChannels(*left, 2);
 
-   project.PushState(_("Created new stereo audio track"), _("New Track"));
+   ProjectManager::Get( project )
+      .PushState(_("Created new stereo audio track"), _("New Track"));
 
    window.RedrawProject();
    trackPanel.EnsureVisible(left);
@@ -866,7 +872,8 @@ void OnNewLabelTrack(const CommandContext &context)
 
    t->SetSelected(true);
 
-   project.PushState(_("Created new label track"), _("New Track"));
+   ProjectManager::Get( project )
+      .PushState(_("Created new label track"), _("New Track"));
 
    window.RedrawProject();
    trackPanel.EnsureVisible(t);
@@ -891,7 +898,8 @@ void OnNewTimeTrack(const CommandContext &context)
 
    t->SetSelected(true);
 
-   project.PushState(_("Created new time track"), _("New Track"));
+   ProjectManager::Get( project )
+      .PushState(_("Created new time track"), _("New Track"));
 
    window.RedrawProject();
    trackPanel.EnsureVisible(t);
@@ -1013,7 +1021,7 @@ void OnResample(const CommandContext &context)
       // commit that to the undo stack.  The second and later times,
       // consolidate.
 
-      project.PushState(
+      ProjectManager::Get( project ).PushState(
          _("Resampled audio track(s)"), _("Resample Track"), flags);
       flags = flags | UndoPush::CONSOLIDATE;
    }
@@ -1047,7 +1055,7 @@ void OnMuteAllTracks(const CommandContext &context)
          pt->SetSolo(false);
    }
 
-   project.ModifyState(true);
+   ProjectManager::Get( project ).ModifyState(true);
    window.RedrawProject();
 }
 
@@ -1068,7 +1076,7 @@ void OnUnmuteAllTracks(const CommandContext &context)
          pt->SetSolo(false);
    }
 
-   project.ModifyState(true);
+   ProjectManager::Get( project ).ModifyState(true);
    window.RedrawProject();
 }
 
@@ -1252,7 +1260,8 @@ void OnSortTime(const CommandContext &context)
    auto &project = context.project;
    DoSortTracks(project, kAudacitySortByTime);
 
-   project.PushState(_("Tracks sorted by time"), _("Sort by Time"));
+   ProjectManager::Get( project )
+      .PushState(_("Tracks sorted by time"), _("Sort by Time"));
 
    auto &trackPanel = TrackPanel::Get( project );
    trackPanel.Refresh(false);
@@ -1263,7 +1272,8 @@ void OnSortName(const CommandContext &context)
    auto &project = context.project;
    DoSortTracks(project, kAudacitySortByName);
 
-   project.PushState(_("Tracks sorted by name"), _("Sort by Name"));
+   ProjectManager::Get( project )
+      .PushState(_("Tracks sorted by name"), _("Sort by Name"));
 
    auto &trackPanel = TrackPanel::Get( project );
    trackPanel.Refresh(false);
diff --git a/src/menus/TransportMenus.cpp b/src/menus/TransportMenus.cpp
index aadbec15b..c599c0b5f 100644
--- a/src/menus/TransportMenus.cpp
+++ b/src/menus/TransportMenus.cpp
@@ -258,7 +258,7 @@ bool DoPlayStopSelect
          // -- change t0, collapsing to point only if t1 was greater
          selection.setT0(time, false);
 
-      project.ModifyState(false);           // without bWantsAutoSave
+      ProjectManager::Get( project ).ModifyState(false);           // without bWantsAutoSave
       return true;
    }
    return false;
@@ -459,7 +459,7 @@ void OnTimerRecord(const CommandContext &context)
       switch (iTimerRecordingOutcome) {
       case POST_TIMER_RECORD_CANCEL_WAIT:
          // Canceled on the wait dialog
-         project.RollbackState();
+         ProjectManager::Get( project ).RollbackState();
          break;
       case POST_TIMER_RECORD_CANCEL:
          // RunWaitDialog() shows the "wait for start" as well as "recording"
@@ -468,7 +468,7 @@ void OnTimerRecord(const CommandContext &context)
          // However, we can't undo it here because the PushState() is called in TrackPanel::OnTimer(),
          // which is blocked by this function.
          // so instead we mark a flag to undo it there.
-         project.SetTimerRecordCancelled();
+         ProjectManager::Get( project ).SetTimerRecordCancelled();
          break;
       case POST_TIMER_RECORD_NOTHING:
          // No action required
@@ -624,7 +624,7 @@ void OnPunchAndRoll(const CommandContext &context)
       ;
    else
       // Roll back the deletions
-      project.RollbackState();
+      ProjectManager::Get( project ).RollbackState();
 }
 #endif
 
diff --git a/src/menus/ViewMenus.cpp b/src/menus/ViewMenus.cpp
index 7740bfa61..5de1147ab 100644
--- a/src/menus/ViewMenus.cpp
+++ b/src/menus/ViewMenus.cpp
@@ -280,7 +280,7 @@ void OnZoomFitV(const CommandContext &context)
 
    window.GetVerticalScrollBar().SetThumbPosition(0);
    window.RedrawProject();
-   project.ModifyState(true);
+   ProjectManager::Get( project ).ModifyState(true);
 }
 
 void OnAdvancedVZoom(const CommandContext &context)
@@ -304,7 +304,7 @@ void OnCollapseAllTracks(const CommandContext &context)
    for (auto t : tracks.Any())
       t->SetMinimized(true);
 
-   project.ModifyState(true);
+   ProjectManager::Get( project ).ModifyState(true);
    window.RedrawProject();
 }
 
@@ -317,7 +317,7 @@ void OnExpandAllTracks(const CommandContext &context)
    for (auto t : tracks.Any())
       t->SetMinimized(false);
 
-   project.ModifyState(true);
+   ProjectManager::Get( project ).ModifyState(true);
    window.RedrawProject();
 }
 
diff --git a/src/tracks/labeltrack/ui/LabelGlyphHandle.cpp b/src/tracks/labeltrack/ui/LabelGlyphHandle.cpp
index a9e9cdbb1..2c6cf09f0 100644
--- a/src/tracks/labeltrack/ui/LabelGlyphHandle.cpp
+++ b/src/tracks/labeltrack/ui/LabelGlyphHandle.cpp
@@ -141,7 +141,7 @@ UIHandle::Result LabelGlyphHandle::Release
    auto &viewInfo = ViewInfo::Get( *pProject );
    if (mpLT->HandleGlyphDragRelease
           (mHit, event, mRect, viewInfo, &viewInfo.selectedRegion)) {
-      pProject->PushState(_("Modified Label"),
+      ProjectManager::Get( *pProject ).PushState(_("Modified Label"),
          _("Label Edit"),
          UndoPush::CONSOLIDATE);
    }
@@ -152,7 +152,7 @@ UIHandle::Result LabelGlyphHandle::Release
 
 UIHandle::Result LabelGlyphHandle::Cancel(AudacityProject *pProject)
 {
-   pProject->RollbackState();
+   ProjectManager::Get( *pProject ).RollbackState();
    auto result = LabelDefaultClickHandle::Cancel( pProject );
    return result | RefreshCode::RefreshAll;
 }
diff --git a/src/tracks/labeltrack/ui/LabelTextHandle.cpp b/src/tracks/labeltrack/ui/LabelTextHandle.cpp
index 6f2a32bfc..5c913e13d 100644
--- a/src/tracks/labeltrack/ui/LabelTextHandle.cpp
+++ b/src/tracks/labeltrack/ui/LabelTextHandle.cpp
@@ -110,7 +110,7 @@ UIHandle::Result LabelTextHandle::Click
    // PRL: bug1659 -- make selection change undo correctly
    const bool unsafe = ProjectAudioIO::Get( *pProject ).IsAudioActive();
    if (!unsafe)
-      pProject->ModifyState(false);
+      ProjectManager::Get( *pProject ).ModifyState(false);
 
    return result | RefreshCode::RefreshCell | RefreshCode::UpdateSelection;
 }
diff --git a/src/tracks/playabletrack/notetrack/ui/NoteTrackButtonHandle.cpp b/src/tracks/playabletrack/notetrack/ui/NoteTrackButtonHandle.cpp
index 7ff878576..94940c92a 100644
--- a/src/tracks/playabletrack/notetrack/ui/NoteTrackButtonHandle.cpp
+++ b/src/tracks/playabletrack/notetrack/ui/NoteTrackButtonHandle.cpp
@@ -102,7 +102,7 @@ UIHandle::Result NoteTrackButtonHandle::Release
    if (pTrack->LabelClick(mRect, event.m_x, event.m_y,
       event.Button(wxMOUSE_BTN_RIGHT))) {
       // No undo items needed??
-      pProject->ModifyState(false);
+      ProjectManager::Get( *pProject ).ModifyState(false);
       return RefreshAll;
    }
    return RefreshNone;
diff --git a/src/tracks/playabletrack/notetrack/ui/NoteTrackControls.cpp b/src/tracks/playabletrack/notetrack/ui/NoteTrackControls.cpp
index 03576ac6d..0c4534309 100644
--- a/src/tracks/playabletrack/notetrack/ui/NoteTrackControls.cpp
+++ b/src/tracks/playabletrack/notetrack/ui/NoteTrackControls.cpp
@@ -116,7 +116,8 @@ void NoteTrackMenuTable::OnChangeOctave(wxCommandEvent &event)
    pTrack->ShiftNoteRange((bDown) ? -12 : 12);
 
    AudacityProject *const project = ::GetActiveProject();
-   project->ModifyState(false);
+   ProjectManager::Get( *project )
+      .ModifyState(false);
    mpData->result = RefreshCode::RefreshAll;
 }
 
diff --git a/src/tracks/playabletrack/notetrack/ui/NoteTrackSliderHandles.cpp b/src/tracks/playabletrack/notetrack/ui/NoteTrackSliderHandles.cpp
index 3bfcb7777..af51686fa 100644
--- a/src/tracks/playabletrack/notetrack/ui/NoteTrackSliderHandles.cpp
+++ b/src/tracks/playabletrack/notetrack/ui/NoteTrackSliderHandles.cpp
@@ -60,7 +60,9 @@ UIHandle::Result VelocitySliderHandle::SetValue
 UIHandle::Result VelocitySliderHandle::CommitChanges
 (const wxMouseEvent &, AudacityProject *pProject)
 {
-   pProject->PushState(_("Moved velocity slider"), _("Velocity"), UndoPush::CONSOLIDATE);
+   ProjectManager::Get( *pProject )
+      .PushState(_("Moved velocity slider"), _("Velocity"),
+         UndoPush::CONSOLIDATE);
    return RefreshCode::RefreshCell;
 }
 
diff --git a/src/tracks/playabletrack/notetrack/ui/NoteTrackVRulerControls.cpp b/src/tracks/playabletrack/notetrack/ui/NoteTrackVRulerControls.cpp
index 09f4556c5..d3dd7187a 100644
--- a/src/tracks/playabletrack/notetrack/ui/NoteTrackVRulerControls.cpp
+++ b/src/tracks/playabletrack/notetrack/ui/NoteTrackVRulerControls.cpp
@@ -81,7 +81,7 @@ unsigned NoteTrackVRulerControls::HandleWheelRotation
       return RefreshNone;
    }
 
-   pProject->ModifyState(false);
+   ProjectManager::Get( *pProject ).ModifyState(false);
 
    return RefreshCell | UpdateVRuler;
 }
diff --git a/src/tracks/playabletrack/notetrack/ui/NoteTrackVZoomHandle.cpp b/src/tracks/playabletrack/notetrack/ui/NoteTrackVZoomHandle.cpp
index 0f0ed8c91..a89ad6b82 100644
--- a/src/tracks/playabletrack/notetrack/ui/NoteTrackVZoomHandle.cpp
+++ b/src/tracks/playabletrack/notetrack/ui/NoteTrackVZoomHandle.cpp
@@ -240,7 +240,7 @@ void NoteTrackVRulerMenuTable::OnZoom( int iZoomCode ){
       mpData->pTrack->ShiftNoteRange(-12);
       break;
    }
-   GetActiveProject()->ModifyState(false);
+   ProjectManager::Get( *GetActiveProject() ).ModifyState(false);
    using namespace RefreshCode;
    mpData->result = UpdateVRuler | RefreshAll;
 }
@@ -341,7 +341,7 @@ UIHandle::Result NoteTrackVZoomHandle::Release
    }
 
    mZoomEnd = mZoomStart = 0;
-   pProject->ModifyState(false);
+   ProjectManager::Get( *pProject ).ModifyState(false);
 
    return RefreshAll;
 }
diff --git a/src/tracks/playabletrack/notetrack/ui/StretchHandle.cpp b/src/tracks/playabletrack/notetrack/ui/StretchHandle.cpp
index f229b1be9..12b3946f9 100644
--- a/src/tracks/playabletrack/notetrack/ui/StretchHandle.cpp
+++ b/src/tracks/playabletrack/notetrack/ui/StretchHandle.cpp
@@ -252,7 +252,7 @@ UIHandle::Result StretchHandle::Release
 
    /* i18n-hint: (noun) The track that is used for MIDI notes which can be
    dragged to change their duration.*/
-   pProject->PushState(_("Stretch Note Track"),
+   ProjectManager::Get( *pProject ).PushState(_("Stretch Note Track"),
       /* i18n-hint: In the history list, indicates a MIDI note has
       been dragged to change its duration (stretch it). Using either past
       or present tense is fine here.  If unsure, go for whichever is
@@ -264,7 +264,7 @@ UIHandle::Result StretchHandle::Release
 
 UIHandle::Result StretchHandle::Cancel(AudacityProject *pProject)
 {
-   pProject->RollbackState();
+   ProjectManager::Get( *pProject ).RollbackState();
    return RefreshCode::RefreshNone;
 }
 
diff --git a/src/tracks/playabletrack/wavetrack/ui/CutlineHandle.cpp b/src/tracks/playabletrack/wavetrack/ui/CutlineHandle.cpp
index dac9213a8..8c2a9ab42 100644
--- a/src/tracks/playabletrack/wavetrack/ui/CutlineHandle.cpp
+++ b/src/tracks/playabletrack/wavetrack/ui/CutlineHandle.cpp
@@ -220,19 +220,21 @@ UIHandle::Result CutlineHandle::Release
    UIHandle::Result result = RefreshCode::RefreshNone;
 
    // Only now commit the result to the undo stack
-   AudacityProject *const project = pProject;
    switch (mOperation) {
    default:
       wxASSERT(false);
    case Merge:
-      project->PushState(_("Merged Clips"), _("Merge"), UndoPush::CONSOLIDATE);
+      ProjectManager::Get( *pProject )
+         .PushState(_("Merged Clips"), _("Merge"), UndoPush::CONSOLIDATE);
       break;
    case Expand:
-      project->PushState(_("Expanded Cut Line"), _("Expand"));
+      ProjectManager::Get( *pProject )
+         .PushState(_("Expanded Cut Line"), _("Expand"));
       result |= RefreshCode::UpdateSelection;
       break;
    case Remove:
-      project->PushState(_("Removed Cut Line"), _("Remove"));
+      ProjectManager::Get( *pProject )
+         .PushState(_("Removed Cut Line"), _("Remove"));
       break;
    }
 
@@ -244,7 +246,7 @@ UIHandle::Result CutlineHandle::Cancel(AudacityProject *pProject)
 {
    using namespace RefreshCode;
    UIHandle::Result result = RefreshCell;
-   pProject->RollbackState();
+   ProjectManager::Get( *pProject ).RollbackState();
    if (mOperation == Expand) {
       AudacityProject &project = *pProject;
       auto &selectedRegion = ViewInfo::Get( project ).selectedRegion;
diff --git a/src/tracks/playabletrack/wavetrack/ui/SampleHandle.cpp b/src/tracks/playabletrack/wavetrack/ui/SampleHandle.cpp
index 0fae1505f..00a8dd0ab 100644
--- a/src/tracks/playabletrack/wavetrack/ui/SampleHandle.cpp
+++ b/src/tracks/playabletrack/wavetrack/ui/SampleHandle.cpp
@@ -434,7 +434,7 @@ UIHandle::Result SampleHandle::Release
    //*************************************************
    //On up-click, send the state to the undo stack
    mClickedTrack.reset();       //Set this to NULL so it will catch improper drag events.
-   pProject->PushState(_("Moved Samples"),
+   ProjectManager::Get( *pProject ).PushState(_("Moved Samples"),
       _("Sample Edit"),
       UndoPush::CONSOLIDATE | UndoPush::AUTOSAVE);
 
@@ -444,7 +444,7 @@ UIHandle::Result SampleHandle::Release
 
 UIHandle::Result SampleHandle::Cancel(AudacityProject *pProject)
 {
-   pProject->RollbackState();
+   ProjectManager::Get( *pProject ).RollbackState();
    mClickedTrack.reset();
    return RefreshCode::RefreshCell;
 }
diff --git a/src/tracks/playabletrack/wavetrack/ui/WaveTrackControls.cpp b/src/tracks/playabletrack/wavetrack/ui/WaveTrackControls.cpp
index db6126d5a..7242dafca 100644
--- a/src/tracks/playabletrack/wavetrack/ui/WaveTrackControls.cpp
+++ b/src/tracks/playabletrack/wavetrack/ui/WaveTrackControls.cpp
@@ -219,7 +219,8 @@ void WaveColorMenuTable::OnWaveColorChange(wxCommandEvent & event)
    for (auto channel : TrackList::Channels(pTrack))
       channel->SetWaveColorIndex(newWaveColor);
 
-   project->PushState(wxString::Format(_("Changed '%s' to %s"),
+   ProjectManager::Get( *project )
+      .PushState(wxString::Format(_("Changed '%s' to %s"),
       pTrack->GetName(),
       GetWaveColorStr(newWaveColor)),
       _("WaveColor Change"));
@@ -337,7 +338,8 @@ void FormatMenuTable::OnFormatChange(wxCommandEvent & event)
       channel->ConvertToSampleFormat(newFormat);
 
    /* i18n-hint: The strings name a track and a format */
-   project->PushState(wxString::Format(_("Changed '%s' to %s"),
+   ProjectManager::Get( *project )
+      .PushState(wxString::Format(_("Changed '%s' to %s"),
       pTrack->GetName(),
       GetSampleFormatStr(newFormat)),
       _("Format Change"));
@@ -438,7 +440,8 @@ void RateMenuTable::SetRate(WaveTrack * pTrack, double rate)
    // Separate conversion of "rate" enables changing the decimals without affecting i18n
    wxString rateString = wxString::Format(wxT("%.3f"), rate);
    /* i18n-hint: The string names a track */
-   project->PushState(wxString::Format(_("Changed '%s' to %s Hz"),
+   ProjectManager::Get( *project )
+      .PushState(wxString::Format(_("Changed '%s' to %s Hz"),
       pTrack->GetName(), rateString),
       _("Rate Change"));
 }
@@ -739,7 +742,7 @@ void WaveTrackMenuTable::OnSetDisplay(wxCommandEvent & event)
       }
 
       AudacityProject *const project = ::GetActiveProject();
-      project->ModifyState(true);
+      ProjectManager::Get( *project ).ModifyState(true);
 
       using namespace RefreshCode;
       mpData->result = RefreshAll | UpdateVRuler;
@@ -794,7 +797,7 @@ void WaveTrackMenuTable::OnSpectrogramSettings(wxCommandEvent &)
    if (0 != dialog.ShowModal()) {
       // Redraw
       AudacityProject *const project = ::GetActiveProject();
-      project->ModifyState(true);
+      ProjectManager::Get( *project ).ModifyState(true);
       //Bug 1725 Toolbar was left greyed out.
       //This solution is overkill, but does fix the problem and is what the
       //prefs dialog normally does.
@@ -880,7 +883,8 @@ void WaveTrackMenuTable::OnMergeStereo(wxCommandEvent &)
       }
 
    /* i18n-hint: The string names a track */
-   project->PushState(wxString::Format(_("Made '%s' a stereo track"),
+   ProjectManager::Get( *project )
+      .PushState(wxString::Format(_("Made '%s' a stereo track"),
       pTrack->GetName()),
       _("Make Stereo"));
 
@@ -948,7 +952,8 @@ void WaveTrackMenuTable::OnSwapChannels(wxCommandEvent &)
       trackPanel.SetFocusedTrack(partner);
 
    /* i18n-hint: The string names a track  */
-   project->PushState(wxString::Format(_("Swapped Channels in '%s'"),
+   ProjectManager::Get( *project )
+      .PushState(wxString::Format(_("Swapped Channels in '%s'"),
       pTrack->GetName()),
       _("Swap Channels"));
 
@@ -962,7 +967,8 @@ void WaveTrackMenuTable::OnSplitStereo(wxCommandEvent &)
    WaveTrack *const pTrack = static_cast<WaveTrack*>(mpData->pTrack);
    AudacityProject *const project = ::GetActiveProject();
    /* i18n-hint: The string names a track  */
-   project->PushState(wxString::Format(_("Split stereo track '%s'"),
+   ProjectManager::Get( *project )
+      .PushState(wxString::Format(_("Split stereo track '%s'"),
       pTrack->GetName()),
       _("Split"));
 
@@ -977,7 +983,8 @@ void WaveTrackMenuTable::OnSplitStereoMono(wxCommandEvent &)
    WaveTrack *const pTrack = static_cast<WaveTrack*>(mpData->pTrack);
    AudacityProject *const project = ::GetActiveProject();
    /* i18n-hint: The string names a track  */
-   project->PushState(wxString::Format(_("Split Stereo to Mono '%s'"),
+   ProjectManager::Get( *project ).
+      PushState(wxString::Format(_("Split Stereo to Mono '%s'"),
       pTrack->GetName()),
       _("Split to Mono"));
 
diff --git a/src/tracks/playabletrack/wavetrack/ui/WaveTrackSliderHandles.cpp b/src/tracks/playabletrack/wavetrack/ui/WaveTrackSliderHandles.cpp
index 7cd0279fe..557d9acf6 100644
--- a/src/tracks/playabletrack/wavetrack/ui/WaveTrackSliderHandles.cpp
+++ b/src/tracks/playabletrack/wavetrack/ui/WaveTrackSliderHandles.cpp
@@ -57,7 +57,8 @@ UIHandle::Result GainSliderHandle::SetValue
 UIHandle::Result GainSliderHandle::CommitChanges
 (const wxMouseEvent &, AudacityProject *pProject)
 {
-   pProject->PushState(_("Moved gain slider"), _("Gain"), UndoPush::CONSOLIDATE);
+   ProjectManager::Get( *pProject )
+      .PushState(_("Moved gain slider"), _("Gain"), UndoPush::CONSOLIDATE);
    return RefreshCode::RefreshCell;
 }
 
@@ -135,7 +136,8 @@ UIHandle::Result PanSliderHandle::SetValue(AudacityProject *pProject, float newV
 UIHandle::Result PanSliderHandle::CommitChanges
 (const wxMouseEvent &, AudacityProject *pProject)
 {
-   pProject->PushState(_("Moved pan slider"), _("Pan"), UndoPush::CONSOLIDATE);
+   ProjectManager::Get( *pProject )
+      .PushState(_("Moved pan slider"), _("Pan"), UndoPush::CONSOLIDATE);
    return RefreshCode::RefreshCell;
 }
 
diff --git a/src/tracks/playabletrack/wavetrack/ui/WaveTrackVRulerControls.cpp b/src/tracks/playabletrack/wavetrack/ui/WaveTrackVRulerControls.cpp
index 1708c65ef..755df43c3 100644
--- a/src/tracks/playabletrack/wavetrack/ui/WaveTrackVRulerControls.cpp
+++ b/src/tracks/playabletrack/wavetrack/ui/WaveTrackVRulerControls.cpp
@@ -186,7 +186,7 @@ unsigned WaveTrackVRulerControls::HandleWheelRotation
    else
       return RefreshNone;
 
-   pProject->ModifyState(true);
+   ProjectManager::Get( *pProject ).ModifyState(true);
 
    return RefreshCell | UpdateVRuler;
 }
diff --git a/src/tracks/playabletrack/wavetrack/ui/WaveTrackVZoomHandle.cpp b/src/tracks/playabletrack/wavetrack/ui/WaveTrackVZoomHandle.cpp
index dda3f1338..0ee52e4cf 100644
--- a/src/tracks/playabletrack/wavetrack/ui/WaveTrackVZoomHandle.cpp
+++ b/src/tracks/playabletrack/wavetrack/ui/WaveTrackVZoomHandle.cpp
@@ -332,7 +332,7 @@ void WaveTrackVZoomHandle::DoZoom
 
    zoomEnd = zoomStart = 0;
    if( pProject )
-      pProject->ModifyState(true);
+      ProjectManager::Get( *pProject ).ModifyState(true);
 }
 
 enum {
@@ -478,7 +478,7 @@ void WaveformVRulerMenuTable::OnWaveformScaleType(wxCommandEvent &evt)
          channel->GetIndependentWaveformSettings().scaleType = newScaleType;
       }
 
-      ::GetActiveProject()->ModifyState(true);
+      ProjectManager::Get( *::GetActiveProject() ).ModifyState(true);
 
       using namespace RefreshCode;
       mpData->result = UpdateVRuler | RefreshAll;
@@ -550,7 +550,7 @@ void SpectrumVRulerMenuTable::OnSpectrumScaleType(wxCommandEvent &evt)
       for (auto channel : TrackList::Channels(wt))
          channel->GetIndependentSpectrogramSettings().scaleType = newScaleType;
 
-      ::GetActiveProject()->ModifyState(true);
+      ProjectManager::Get( *::GetActiveProject() ).ModifyState(true);
 
       using namespace RefreshCode;
       mpData->result = UpdateVRuler | RefreshAll;
diff --git a/src/tracks/timetrack/ui/TimeTrackControls.cpp b/src/tracks/timetrack/ui/TimeTrackControls.cpp
index 4bb5ddced..e07529413 100644
--- a/src/tracks/timetrack/ui/TimeTrackControls.cpp
+++ b/src/tracks/timetrack/ui/TimeTrackControls.cpp
@@ -104,7 +104,8 @@ void TimeTrackMenuTable::OnSetTimeTrackRange(wxCommandEvent & /*event*/)
          AudacityProject *const project = ::GetActiveProject();
          pTrack->SetRangeLower((double)lower / 100.0);
          pTrack->SetRangeUpper((double)upper / 100.0);
-         project->PushState(wxString::Format(_("Set range to '%ld' - '%ld'"),
+         ProjectManager::Get( *project )
+            .PushState(wxString::Format(_("Set range to '%ld' - '%ld'"),
             lower,
             upper),
             /* i18n-hint: (verb)*/
@@ -119,7 +120,8 @@ void TimeTrackMenuTable::OnTimeTrackLin(wxCommandEvent & /*event*/)
    TimeTrack *const pTrack = static_cast<TimeTrack*>(mpData->pTrack);
    pTrack->SetDisplayLog(false);
    AudacityProject *const project = ::GetActiveProject();
-   project->PushState(_("Set time track display to linear"), _("Set Display"));
+   ProjectManager::Get( *project )
+      .PushState(_("Set time track display to linear"), _("Set Display"));
 
    using namespace RefreshCode;
    mpData->result = RefreshAll | UpdateVRuler;
@@ -130,7 +132,8 @@ void TimeTrackMenuTable::OnTimeTrackLog(wxCommandEvent & /*event*/)
    TimeTrack *const pTrack = static_cast<TimeTrack*>(mpData->pTrack);
    pTrack->SetDisplayLog(true);
    AudacityProject *const project = ::GetActiveProject();
-   project->PushState(_("Set time track display to logarithmic"), _("Set Display"));
+   ProjectManager::Get( *project )
+      .PushState(_("Set time track display to logarithmic"), _("Set Display"));
 
    using namespace RefreshCode;
    mpData->result = RefreshAll | UpdateVRuler;
@@ -142,11 +145,13 @@ void TimeTrackMenuTable::OnTimeTrackLogInt(wxCommandEvent & /*event*/)
    AudacityProject *const project = ::GetActiveProject();
    if (pTrack->GetInterpolateLog()) {
       pTrack->SetInterpolateLog(false);
-      project->PushState(_("Set time track interpolation to linear"), _("Set Interpolation"));
+      ProjectManager::Get( *project )
+         .PushState(_("Set time track interpolation to linear"), _("Set Interpolation"));
    }
    else {
       pTrack->SetInterpolateLog(true);
-      project->PushState(_("Set time track interpolation to logarithmic"), _("Set Interpolation"));
+      ProjectManager::Get( *project ).
+         PushState(_("Set time track interpolation to logarithmic"), _("Set Interpolation"));
    }
    mpData->result = RefreshCode::RefreshAll;
 }
diff --git a/src/tracks/ui/EnvelopeHandle.cpp b/src/tracks/ui/EnvelopeHandle.cpp
index 8b19d3827..c9060c6d9 100644
--- a/src/tracks/ui/EnvelopeHandle.cpp
+++ b/src/tracks/ui/EnvelopeHandle.cpp
@@ -287,7 +287,7 @@ UIHandle::Result EnvelopeHandle::Release
 
    const bool needUpdate = ForwardEventToEnvelopes(event, viewInfo);
 
-   pProject->PushState(
+   ProjectManager::Get( *pProject ).PushState(
       /* i18n-hint: (verb) Audacity has just adjusted the envelope .*/
       _("Adjusted envelope."),
       /* i18n-hint: The envelope is a curve that controls the audio loudness.*/
@@ -302,7 +302,7 @@ UIHandle::Result EnvelopeHandle::Release
 
 UIHandle::Result EnvelopeHandle::Cancel(AudacityProject *pProject)
 {
-   pProject->RollbackState();
+   ProjectManager::Get( *pProject ).RollbackState();
    mEnvelopeEditors.clear();
    return RefreshCode::RefreshCell;
 }
diff --git a/src/tracks/ui/SelectHandle.cpp b/src/tracks/ui/SelectHandle.cpp
index 0f4066481..619505ce2 100644
--- a/src/tracks/ui/SelectHandle.cpp
+++ b/src/tracks/ui/SelectHandle.cpp
@@ -579,7 +579,7 @@ UIHandle::Result SelectHandle::Click
          }
       } );
 
-      pProject->ModifyState(false);
+      ProjectManager::Get( *pProject ).ModifyState(false);
 
       // Do not start a drag
       return RefreshAll | UpdateSelection | Cancelled;
@@ -664,7 +664,7 @@ UIHandle::Result SelectHandle::Click
       };
 
       // For persistence of the selection change:
-      pProject->ModifyState(false);
+      ProjectManager::Get( *pProject ).ModifyState(false);
 
       // Get timer events so we can auto-scroll
       Connect(pProject);
@@ -702,7 +702,7 @@ UIHandle::Result SelectHandle::Click
                static_cast<WaveTrack*>(pTrack),
                viewInfo, event.m_y, mRect.y, mRect.height);
             // For persistence of the selection change:
-            pProject->ModifyState(false);
+            ProjectManager::Get( *pProject ).ModifyState(false);
             mSelectionBoundary = SBWidth;
             return UpdateSelection;
          }
@@ -986,7 +986,7 @@ UIHandle::Result SelectHandle::Release
  wxWindow *)
 {
    using namespace RefreshCode;
-   pProject->ModifyState(false);
+   ProjectManager::Get( *pProject ).ModifyState(false);
    mFrequencySnapper.reset();
    mSnapManager.reset();
    if (mSelectionStateChanger) {
@@ -1126,7 +1126,7 @@ void SelectHandle::StartSelection( AudacityProject *pProject )
    // PRL:  commented out the Sonify stuff with the TrackPanel refactor.
    // It was no-op anyway.
    //SonifyBeginModifyState();
-   pProject->ModifyState(false);
+   ProjectManager::Get( *pProject ).ModifyState(false);
    //SonifyEndModifyState();
 }
 
diff --git a/src/tracks/ui/TimeShiftHandle.cpp b/src/tracks/ui/TimeShiftHandle.cpp
index 6fc43ba00..d5eee9489 100644
--- a/src/tracks/ui/TimeShiftHandle.cpp
+++ b/src/tracks/ui/TimeShiftHandle.cpp
@@ -835,7 +835,7 @@ UIHandle::Result TimeShiftHandle::Release
          fabs( mClipMoveState.hSlideAmount ) );
       consolidate = true;
    }
-   pProject->PushState(msg, _("Time-Shift"),
+   ProjectManager::Get( *pProject ).PushState(msg, _("Time-Shift"),
       consolidate ? (UndoPush::CONSOLIDATE) : (UndoPush::AUTOSAVE));
 
    return result | FixScrollbars;
@@ -843,7 +843,7 @@ UIHandle::Result TimeShiftHandle::Release
 
 UIHandle::Result TimeShiftHandle::Cancel(AudacityProject *pProject)
 {
-   pProject->RollbackState();
+   ProjectManager::Get( *pProject ).RollbackState();
    return RefreshCode::RefreshAll;
 }
 
diff --git a/src/tracks/ui/TrackButtonHandles.cpp b/src/tracks/ui/TrackButtonHandles.cpp
index 985d0d21b..b9b65e481 100644
--- a/src/tracks/ui/TrackButtonHandles.cpp
+++ b/src/tracks/ui/TrackButtonHandles.cpp
@@ -39,7 +39,7 @@ UIHandle::Result MinimizeButtonHandle::CommitChanges
       bool wasMinimized = pTrack->GetMinimized();
       for (auto channel : TrackList::Channels(pTrack.get()))
          channel->SetMinimized(!wasMinimized);
-      pProject->ModifyState(true);
+      ProjectManager::Get( *pProject ).ModifyState(true);
 
       // Redraw all tracks when any one of them expands or contracts
       // (Could we invent a return code that draws only those at or below
diff --git a/src/tracks/ui/TrackControls.cpp b/src/tracks/ui/TrackControls.cpp
index d4d907160..045fec503 100644
--- a/src/tracks/ui/TrackControls.cpp
+++ b/src/tracks/ui/TrackControls.cpp
@@ -221,7 +221,8 @@ void TrackMenuTable::OnSetName(wxCommandEvent &)
          for (auto channel : TrackList::Channels(pTrack))
             channel->SetName(newName);
 
-         proj->PushState(wxString::Format(_("Renamed '%s' to '%s'"),
+         ProjectManager::Get( *proj )
+            .PushState(wxString::Format(_("Renamed '%s' to '%s'"),
             oldName,
             newName),
             _("Name Change"));
diff --git a/src/tracks/ui/TrackSelectHandle.cpp b/src/tracks/ui/TrackSelectHandle.cpp
index 927c4e045..661b10288 100644
--- a/src/tracks/ui/TrackSelectHandle.cpp
+++ b/src/tracks/ui/TrackSelectHandle.cpp
@@ -180,7 +180,7 @@ UIHandle::Result TrackSelectHandle::Release
    wxASSERT( mpTrack );
    if (mRearrangeCount != 0) {
       AudacityProject *const project = ::GetActiveProject();
-      project->PushState(
+      ProjectManager::Get( *project ).PushState(
          wxString::Format(
             /* i18n-hint: will substitute name of track for %s */
             ( mRearrangeCount < 0 ? _("Moved '%s' up") : _("Moved '%s' down") ),
@@ -199,7 +199,7 @@ UIHandle::Result TrackSelectHandle::Release
 
 UIHandle::Result TrackSelectHandle::Cancel(AudacityProject *pProject)
 {
-   pProject->RollbackState();
+   ProjectManager::Get( *pProject ).RollbackState();
    // Bug 1677
    mpTrack.reset();
    return RefreshCode::RefreshAll;