The goal of the Authorization and Access Control Working Group is to develop guidelines and an Application Programming Interface (API) through which network accessible applications can uniformly specify access control information. This API will allow applications to make access control decisions when clients are not local users, might not be members of a common organization, and often not known to the service or application in advance. Several authentication mechanisms are in place on the Internet, but most applications are written with local applications in mind and no guidelines exist for supporting authorization and access control based on the output of such authentication mechanisms. The CAT Working Group developed the GSS-API, a common API to support authentication. The AAC Working Group will develop a common API that accepts the identity of a client (perhaps the output of the GSS-API), a reference to an object to be accessed, and optionally an indication of the operation to be performed. The API will return a list of authorized operations or a yes/no answer that can be easily used by the application. A second, longer term purpose of the working group will be to examine evolving mechanisms and architectures for authorization in distributed systems and to establish criteria which enable interworking of confidence and trust across systems. The working group will develop additional goals and milestones related to this purpose and will submit a revised charter once the appropriate goals and milestones are determined. To the extent possible this additional work will encourage evolution toward credential formats that more readily allow support for or translation across multiple mechanisms.