I have a RadTreeView drag and drop prototype. It looks like that somehow the DragQueryHandler is not called, i.e. when I put a break point in the handler, the app never hit the break point when debugging. What could be the problem? The item seems to drag over fine though. However, I would like to have the TreeView item and all of its children to drag over so I would need to manipulate the e.Payload property in the DragQueryHandler. Is there a property setting that makes it automatically bring the selected TreeView item and its children over?