I am using the RadTreeView in a 2-pane splitter as the primary navigation item for editing items. In the other pane, I am displaying a Property Grid to edit an item's contents. When the user attempts to select another treeItem, I want to display a message asking to save. Depending on the user's response, I want to prevent the RadtreeView from selecting the new item and have it continue to display the prior item as if nothing happened (e.g, the prior item should still be highlighted and focused). At first, I thought the PreviewSelect and/or PreviewUnselect would do the trick, but they don't seem to work completely. They don't really stop the event chain and things are left in a semi-selected state. Even though the tree is set up for single select mode, using those events ends up with 2 items selected. Any suggestions?