diff --git a/radiant/ui/materials/editor/MaterialEditor.cpp b/radiant/ui/materials/editor/MaterialEditor.cpp
index 0038fbfb1c..c71779c332 100644
--- a/radiant/ui/materials/editor/MaterialEditor.cpp
+++ b/radiant/ui/materials/editor/MaterialEditor.cpp
@@ -348,7 +348,7 @@ void MaterialEditor::_onReloadImages(wxCommandEvent& ev)
     _material->refreshImageMaps();
 }
 
-void MaterialEditor::_onClose(wxCommandEvent& ev)
+bool MaterialEditor::okToCloseDialog()
 {
     // Check all unsaved materials
     std::list<MaterialPtr> modifiedMaterials;
@@ -367,12 +367,27 @@ void MaterialEditor::_onClose(wxCommandEvent& ev)
         // Prompt user to save or discard
         if (!askUserAboutModifiedMaterial())
         {
-            return; // cancel the close event
+            return false; // cancel the close event
         }
     }
 
     // At this point, everything is saved
-    EndModal(wxID_CLOSE);
+    return true;
+}
+
+bool MaterialEditor::_onDeleteEvent()
+{
+    // Return true if preClose() vetoes the close event
+    return !okToCloseDialog();
+}
+
+void MaterialEditor::_onClose(wxCommandEvent& ev)
+{
+    // Check if it's ok to close the dialog
+    if (okToCloseDialog())
+    {
+        EndModal(wxID_CLOSE);
+    }
 }
 
 void MaterialEditor::ShowDialog(const cmd::ArgumentList& args)
diff --git a/radiant/ui/materials/editor/MaterialEditor.h b/radiant/ui/materials/editor/MaterialEditor.h
index 1f8d559fe8..40974573c8 100644
--- a/radiant/ui/materials/editor/MaterialEditor.h
+++ b/radiant/ui/materials/editor/MaterialEditor.h
@@ -100,10 +100,15 @@ class MaterialEditor :
 
     static void ShowDialog(const cmd::ArgumentList& args);
 
-    void _onClose(wxCommandEvent& ev);
-    void _onReloadImages(wxCommandEvent& ev);
+protected:
+    // Intercept close commands from pressing ESC keys
+    bool _onDeleteEvent() override;
 
 private:
+    // Asks user to save each unmodified material.
+    // Returns true if it is safe to go ahead and close the dialog
+    bool okToCloseDialog();
+
     void setupBasicMaterialPage();
     void setupMaterialTreeView();
     void setupMaterialStageView();
@@ -196,6 +201,8 @@ class MaterialEditor :
     void _onBasicAddFrobStages(wxCommandEvent& ev);
     void _onBasicRemoveFrobStages(wxCommandEvent& ev);
     void _onBasicTestFrobStages(wxMouseEvent& ev);
+    void _onClose(wxCommandEvent& ev);
+    void _onReloadImages(wxCommandEvent& ev);
 
     void toggleSelectedStage();
     void onMaterialChanged();