diff --git a/common/eda_base_frame.cpp b/common/eda_base_frame.cpp
index 6da082859c..ba66474d1e 100644
--- a/common/eda_base_frame.cpp
+++ b/common/eda_base_frame.cpp
@@ -47,6 +47,8 @@
 #include <wx/stdpaths.h>
 #include <wx/string.h>
 
+wxDEFINE_EVENT( UNITS_CHANGED, wxCommandEvent );
+
 
 // Minimum window size
 static const int s_minsize_x = 500;
@@ -738,3 +740,12 @@ bool EDA_BASE_FRAME::IsContentModified()
     // This function should be overridden in child classes
     return false;
 }
+
+void EDA_BASE_FRAME::ChangeUserUnits( EDA_UNITS aUnits )
+{
+    SetUserUnits( aUnits );
+    unitsChangeRefresh();
+
+    wxCommandEvent e( UNITS_CHANGED );
+    ProcessEventLocally( e );
+}
diff --git a/include/eda_base_frame.h b/include/eda_base_frame.h
index bacaf69746..c081da9a88 100644
--- a/include/eda_base_frame.h
+++ b/include/eda_base_frame.h
@@ -88,6 +88,8 @@ enum id_librarytype {
     LIBRARY_TYPE_SYMBOL
 };
 
+wxDECLARE_EVENT( UNITS_CHANGED, wxCommandEvent );
+
 
 /**
  * The base frame for deriving all KiCad main window classes.
@@ -209,11 +211,7 @@ public:
         m_userUnits = aUnits;
     }
 
-    void ChangeUserUnits( EDA_UNITS aUnits )
-    {
-        SetUserUnits( aUnits );
-        unitsChangeRefresh();
-    }
+    void ChangeUserUnits( EDA_UNITS aUnits );
 
     SETTINGS_MANAGER* GetSettingsManager() const { return m_settingsManager; }
 
diff --git a/include/pcb_base_frame.h b/include/pcb_base_frame.h
index 6cd3eb97cf..01b00e812c 100644
--- a/include/pcb_base_frame.h
+++ b/include/pcb_base_frame.h
@@ -61,6 +61,9 @@ class PCB_PLOT_PARAMS;
 class FP_LIB_TABLE;
 class PCBNEW_SETTINGS;
 
+
+wxDECLARE_EVENT( BOARD_CHANGED, wxCommandEvent );
+
 /**
  * PCB_BASE_FRAME
  * basic PCB main window class for Pcbnew, Gerbview, and CvPcb footprint viewer.
diff --git a/pcbnew/pcb_base_frame.cpp b/pcbnew/pcb_base_frame.cpp
index 13d5bb20e5..2293dffc40 100644
--- a/pcbnew/pcb_base_frame.cpp
+++ b/pcbnew/pcb_base_frame.cpp
@@ -54,6 +54,7 @@
 #include <tool/tool_dispatcher.h>
 #include <tools/pcb_actions.h>
 
+wxDEFINE_EVENT( BOARD_CHANGED, wxCommandEvent );
 
 BEGIN_EVENT_TABLE( PCB_BASE_FRAME, EDA_DRAW_FRAME )
     EVT_TOOL( ID_TB_OPTIONS_SHOW_PADS_SKETCH, PCB_BASE_FRAME::OnTogglePadDrawMode )
@@ -158,6 +159,9 @@ void PCB_BASE_FRAME::SetBoard( BOARD* aBoard )
         delete m_Pcb;
         m_Pcb = aBoard;
         m_Pcb->SetGeneralSettings( m_Settings );
+
+        wxCommandEvent e( BOARD_CHANGED );
+        ProcessEventLocally( e );
     }
 }