diff --git a/plug-ins/pluck.ny b/plug-ins/pluck.ny
index eb52daab7..831f83756 100644
--- a/plug-ins/pluck.ny
+++ b/plug-ins/pluck.ny
@@ -3,6 +3,7 @@
 ;type generate
 ;categories "http://lv2plug.in/ns/lv2core#GeneratorPlugin"
 ;name "Pluck..."
+;help "Pluck"
 ;preview linear
 ;action "Generating pluck sound..."
 ;info "MIDI values for C notes: 36, 48, 60 [middle C], 72, 84, 96."
diff --git a/src/effects/Amplify.cpp b/src/effects/Amplify.cpp
index 995b29c2a..eed486680 100644
--- a/src/effects/Amplify.cpp
+++ b/src/effects/Amplify.cpp
@@ -90,6 +90,11 @@ wxString EffectAmplify::GetDescription()
    return XO("Increases or decreases the volume of the audio you have selected");
 }
 
+wxString EffectAmplify::HelpPageName()
+{
+   return wxT("Amplify");
+}
+
 // EffectIdentInterface implementation
 
 EffectType EffectAmplify::GetType()
diff --git a/src/effects/Amplify.h b/src/effects/Amplify.h
index 017b80e33..1f5d523ac 100644
--- a/src/effects/Amplify.h
+++ b/src/effects/Amplify.h
@@ -37,6 +37,7 @@ public:
 
    wxString GetSymbol() override;
    wxString GetDescription() override;
+   wxString HelpPageName() override;
 
    // EffectIdentInterface implementation
 
diff --git a/src/effects/Effect.cpp b/src/effects/Effect.cpp
index 328cfa466..10167ede6 100644
--- a/src/effects/Effect.cpp
+++ b/src/effects/Effect.cpp
@@ -53,6 +53,7 @@ greater use in future.
 #include "../ondemand/ODManager.h"
 #include "TimeWarper.h"
 #include "nyquist/Nyquist.h"
+#include "../widgets/HelpSystem.h"
 
 #if defined(__WXMAC__)
 #include <Cocoa/Cocoa.h>
@@ -1098,6 +1099,11 @@ wxString Effect::GetPreset(wxWindow * parent, const wxString & parms)
    return wxEmptyString;
 }
 
+wxString Effect::HelpPageName()
+{
+   return wxEmptyString;
+}
+
 bool Effect::IsBatchProcessing()
 {
    return mIsBatch;
@@ -2767,6 +2773,7 @@ BEGIN_EVENT_TABLE(EffectUIHost, wxDialogWrapper)
    EVT_CLOSE(EffectUIHost::OnClose)
    EVT_BUTTON(wxID_APPLY, EffectUIHost::OnApply)
    EVT_BUTTON(wxID_CANCEL, EffectUIHost::OnCancel)
+   EVT_BUTTON(wxID_HELP, EffectUIHost::OnHelp)
    EVT_BUTTON(eDebugID, EffectUIHost::OnDebug)
    EVT_BUTTON(kMenuID, EffectUIHost::OnMenu)
    EVT_CHECKBOX(kEnableID, EffectUIHost::OnEnable)
@@ -3039,13 +3046,23 @@ bool EffectUIHost::Initialize()
          bar->SetSizerAndFit(bs.release());
       }
 
-      // TODO: Add Help button
-      // long buttons = eApplyButton + eCloseButton + eHelpButton;
-      long buttons = eApplyButton + eCloseButton;
-      if (mEffect->mUIDebug)
-      {
-         buttons += eDebugButton;
+      long buttons;
+      if ( !(mEffect->HelpPageName().IsEmpty())) {
+         buttons = eApplyButton + eCloseButton + eHelpButton;
+         wxAcceleratorEntry entries[1];
+#if defined(__WXMAC__)
+         entries[0].Set(wxACCEL_CTRL, (int) '?', wxID_HELP);
+#else
+         entries[0].Set(wxACCEL_NORMAL, (int) WXK_F1, wxID_HELP);
+#endif
+         wxAcceleratorTable accel(1, entries);
+         this->SetAcceleratorTable(accel);
       }
+      else {
+         buttons = eApplyButton + eCloseButton;
+         this->SetAcceleratorTable(wxNullAcceleratorTable);
+      }
+
 
       buttonPanel->SetSizer(CreateStdButtonSizer(buttonPanel, buttons, bar).release());
       vs->Add(buttonPanel, 0, wxEXPAND);
@@ -3205,6 +3222,11 @@ void EffectUIHost::OnCancel(wxCommandEvent & evt)
    return;
 }
 
+void EffectUIHost::OnHelp(wxCommandEvent & WXUNUSED(event))
+{
+   HelpSystem::ShowHelpDialog(this, mEffect->HelpPageName(), true);
+}
+
 void EffectUIHost::OnDebug(wxCommandEvent & evt)
 {
    OnApply(evt);
diff --git a/src/effects/Effect.h b/src/effects/Effect.h
index df57c9dcb..c12bfbf5e 100644
--- a/src/effects/Effect.h
+++ b/src/effects/Effect.h
@@ -226,6 +226,8 @@ class AUDACITY_DLL_API Effect /* not final */ : public wxEvtHandler,
    virtual bool HasFactoryDefaults();
    virtual wxString GetPreset(wxWindow * parent, const wxString & parms);
 
+   virtual wxString HelpPageName();
+
    virtual bool IsBatchProcessing();
    virtual void SetBatchProcessing(bool start);
 
@@ -593,6 +595,7 @@ private:
    void OnApply(wxCommandEvent & evt);
    void DoCancel();
    void OnCancel(wxCommandEvent & evt);
+   void OnHelp(wxCommandEvent & evt);
    void OnDebug(wxCommandEvent & evt);
    void OnMenu(wxCommandEvent & evt);
    void OnEnable(wxCommandEvent & evt);
diff --git a/src/effects/nyquist/Nyquist.cpp b/src/effects/nyquist/Nyquist.cpp
index efe188045..146553286 100644
--- a/src/effects/nyquist/Nyquist.cpp
+++ b/src/effects/nyquist/Nyquist.cpp
@@ -212,6 +212,11 @@ wxString NyquistEffect::GetDescription()
    return mCopyright;
 }
 
+wxString NyquistEffect::HelpPageName()
+{
+   return mHelpFile;
+}
+
 // EffectIdentInterface implementation
 
 EffectType NyquistEffect::GetType()
@@ -1607,6 +1612,11 @@ void NyquistEffect::Parse(const wxString &line)
       return;
    }
 
+   if (len >= 2 && tokens[0] == wxT("help")) {
+      mHelpFile = UnQuote(tokens[1]);
+      return;
+   }
+
    if (len >= 6 && tokens[0] == wxT("control")) {
       NyqControl ctrl;
 
@@ -1719,6 +1729,7 @@ bool NyquistEffect::ParseProgram(wxInputStream & stream)
    mControls.Clear();
    mCategories.Clear();
    mIsSpectral = false;
+   mHelpFile = wxEmptyString; // If not wxEmptyString, must be a valid HTML help file.
 
    mFoundType = false;
    while (!stream.Eof() && stream.IsOk())
diff --git a/src/effects/nyquist/Nyquist.h b/src/effects/nyquist/Nyquist.h
index 6db9e0b04..0e2e41386 100644
--- a/src/effects/nyquist/Nyquist.h
+++ b/src/effects/nyquist/Nyquist.h
@@ -79,6 +79,7 @@ public:
    wxString GetVendor() override;
    wxString GetVersion() override;
    wxString GetDescription() override;
+   wxString HelpPageName() override;
 
    // EffectIdentInterface implementation
 
@@ -194,6 +195,7 @@ private:
    wxString          mInfo;
    wxString          mAuthor;
    wxString          mCopyright;
+   wxString          mHelpFile;
    EffectType        mType;
 
    bool              mEnablePreview;
diff --git a/src/prefs/PrefsDialog.cpp b/src/prefs/PrefsDialog.cpp
index 61db75d53..f874c39e7 100644
--- a/src/prefs/PrefsDialog.cpp
+++ b/src/prefs/PrefsDialog.cpp
@@ -118,19 +118,20 @@ int wxTreebookExt::SetSelection(size_t n)
    wxWindow *const applyButton = wxWindow::FindWindowById(wxID_APPLY, GetParent());
 
    if (helpButton) {
-#if defined(__WXMAC__)
-      // We don't appear to have accelerators on wxMac
-#else
       if (showHelp) {
          wxAcceleratorEntry entries[1];
-         entries[0].Set(wxACCEL_ALT, (int) 'H', wxID_HELP);
+#if defined(__WXMAC__)
+         entries[0].Set(wxACCEL_CTRL, (int) '?', wxID_HELP);
+#else
+         entries[0].Set(wxACCEL_NORMAL, (int) WXK_F1, wxID_HELP);
+#endif
          wxAcceleratorTable accel(1, entries);
          this->SetAcceleratorTable(accel);
       }
       else {
          this->SetAcceleratorTable(wxNullAcceleratorTable);
       }
-#endif
+
       const bool changed = helpButton->Show(showHelp);
       if (changed)
          GetParent()->Layout();