diff --git a/src/mac/carbon/dialog.cpp b/src/mac/carbon/dialog.cpp
index 7b7bfc024b..cab8d1906c 100644
--- a/src/mac/carbon/dialog.cpp
+++ b/src/mac/carbon/dialog.cpp
@@ -78,6 +78,9 @@ void wxDialog::SetModal(bool flag)
         m_windowStyle |= wxDIALOG_MODAL;
         
         wxModelessWindows.DeleteObject(this);
+#if TARGET_CARBON
+        SetWindowModality( (WindowRef) MacGetWindowRef() , kWindowModalityAppModal , NULL ) ;
+#endif
     }
     else
     {
diff --git a/src/mac/dialog.cpp b/src/mac/dialog.cpp
index 7b7bfc024b..cab8d1906c 100644
--- a/src/mac/dialog.cpp
+++ b/src/mac/dialog.cpp
@@ -78,6 +78,9 @@ void wxDialog::SetModal(bool flag)
         m_windowStyle |= wxDIALOG_MODAL;
         
         wxModelessWindows.DeleteObject(this);
+#if TARGET_CARBON
+        SetWindowModality( (WindowRef) MacGetWindowRef() , kWindowModalityAppModal , NULL ) ;
+#endif
     }
     else
     {