Abstract: A method and system are provided for authenticating users in a client-server system in a way that allows a user to sign-on to numerous servers using a different password for each server, while still only having to remember a single master password. According to one aspect of the invention, a client generates a first set of server-specific authentication information for a first server based on master authentication information stored at the client and data associated with the first server. The client then supplies the first server-specific authentication information to the first server to access restricted resources controlled by the first server. The client generates a second set of second server-specific authentication information for a second server based on the same master authentication information. However, to generate the server-specific authentication information for the second server, the master resource information is combined with data associated with the second server.