Hi, We don't have a dedicated Refresh() method (one is already planned for SP2 or 2009.2 release, whichever comes first), but you can use the following (admittedly, not very intuitive) workaround: parentNode.IsExpanded = false; parentNode.IsLoadOnDemandCompleted = false; parentNode.IsLoadOnDemandEnabled = false; parentNode.IsLoadOnDemandEnabled = true; parentNode.Items.Clear(); parentNode.Dispatcher.BeginInvoke(() => { parentNode.IsExpanded = true; }); Refreshing the whole TreeView is more...