I have a web application (.NET 3.5) that has this code in Global.asax: Sub Application_BeginRequest(ByVal sender As Object, ByVal e As EventArgs) LinkLoader() PathRewriter() PathAppender() End Sub I want all those functions inside to get called except for when it's an AJAX call back. So, ideally I would have it changed to: Sub Application_BeginRequest(ByVal sender As Object, ByVal e As EventArgs) If not Page.IsCallback then LinkLoader() PathRewriter() PathAppender() End If End Sub But there is not access to the page object here. So, basically my question is: How do I check if the request is an AJAX call back inside Application_BeginRequest? Thank you very much for any feedback.