1. A method of providing a unified access to systems, the method including: storing a plurality of sets of user credentials for a plurality of remote computer applications in a central repository accessible via an interoperability network, wherein the plurality of remote computer applications are entities that do not share a common identity verification protocol; receiving an interoperability network credential that authorizes a user to use the plurality of remote computer applications and access the stored plurality of sets of the user credentials; verifying that an intermediary service coupled to the interoperability network, upon receiving a request to perform, on behalf of the user, a particular task that requires access to and task performance by a particular remote computer application from the plurality of remote computer applications, has authorization to act on behalf of the user in obtaining authorized access to and task performance by the particular remote computer application; and upon verification of authorization, automatically supplying the intermediary service particular user credentials for the particular remote computer application from the central repository.