We are using treeview as a user hierarchy with remote data via ajax; if there are several people working on the treeview at the same time, moving users around, what happens if, for example, 'User B' moves someone around in the UI if they have already been moved (without knowledge) that 'User A' had moved them elsewhere.. Our assumption is that the last user to make an edit would be authoritative; confirm or deny? Also, is there some error checking that we can plug into this?