Server.Transfer bypasses the authorization for the page you redirect to. So if you use Server.Transfer instead of Response.Redirect (for other pros and cons of each see this article on managing navigation in ASP.NET by the excellent Mike Gunderloy), make sure that the authorization to access the target page is performed before the call to Server.Transfer. If you use Response.Redirect, you do not have to worry about this. Yet another reason why I almost always use Response.Redirect.