diff --git a/src/Editor/Undo/IEditPropertyCommand.cpp b/src/Editor/Undo/IEditPropertyCommand.cpp
index a6609823..7996785f 100644
--- a/src/Editor/Undo/IEditPropertyCommand.cpp
+++ b/src/Editor/Undo/IEditPropertyCommand.cpp
@@ -75,7 +75,7 @@ void IEditPropertyCommand::SaveNewData()
     mSavedNewData = true;
 }
 
-bool IEditPropertyCommand::IsNewDataDifferent()
+bool IEditPropertyCommand::IsNewDataDifferent() const
 {
     if (mOldData.size() != mNewData.size()) return true;
     return memcmp(mOldData.data(), mNewData.data(), mNewData.size()) != 0;
diff --git a/src/Editor/Undo/IEditPropertyCommand.h b/src/Editor/Undo/IEditPropertyCommand.h
index 5876de71..c3021983 100644
--- a/src/Editor/Undo/IEditPropertyCommand.h
+++ b/src/Editor/Undo/IEditPropertyCommand.h
@@ -40,7 +40,7 @@ public:
     virtual void SaveOldData();
     virtual void SaveNewData();
 
-    bool IsNewDataDifferent();
+    bool IsNewDataDifferent() const;
     void SetEditComplete(bool IsComplete);
 
     /** Interface */