Abstract: A credential security support provider (Cred SSP) is provided that enables any application to securely delegate a user's credentials from the client, via client side Security Support Provider (SSP) software, to a target server, via server side SSP software in a networked computing environment. The Cred SSP of the invention provides a secure solution that is based in part upon a set of policies, including a default policy that is secure against a broad range of attacks, which are used to control and restrict the delegation of user credentials from a client to a server. The policies can be for any type of user credentials and the different policies are designed to mitigate a broad range of attacks so that appropriate delegation can occur for given delegation circumstances, network conditions, trust levels, etc. Additionally, only a trusted subsystem, e.g.