This disclosure pertains generally to client authentication. One aspect of the disclosure relates to a first server for presenting evidence to a Domain Controller (DC) of a first authentication context being submitted from a client to the first server to obtain a delegable credential, wherein the credential can be used to request a second authentication context from that client to a second server. Another aspect relates to the first server providing a pass-thru with evidence to a DC. The evidence relates to a first authentication context being submitted from a client to the first server that it obtained a delegable credential. The pass-thru is used in combination with the credential to request a second authentication context from the client to a second server.