I have a webpage that contains a very simple user control and an html based treeview contained within an ASP.net label control. The treeview is very complex and takes a long time to render from ViewState upon loading the page after postback. I want to update the simple user control which requires a roundtrip to the server. This update should take less than a second but because it has to reload the treeview from viewstate it takes 3-4 seconds. Is it possible to update the usercontrol without posting back the parent page. I don't want to make any changes to the parent page outside of the user control.