hi Type represents declarations.So why Type objects only represent some types and not others? This throws Null reference exception Type type=Type.GetType("System.Data.SqlClient.SqlCommand"); MemberInfo[] memInfo=type.GetMembers(); foreach(MemberInfo mi1 in memInfo) { Console.WriteLine(mi1); } So why do we have a Type object that represents StreamWriter class but we don't have one representing SqlCommand or DataSet class?I actually thought Type object can be created for all types,even user defined types thanx