in .net 3.5 Microsoft has introduced Applicaton Service through WCF. This includes Authentication Service, Role Provider Service and Profiler Service. Now I am having a requirement that force me to add one more Function in AuthenticationService class. But I have found that AuthenticationService Class have no public Constructor. Thus it cannot be inherited. So is there any other way, I can add one more function into System.Web.ApplicationServices.AuthenticationService class.