This paper describes a use case based access control architecture developed by the authors that is extensible and provides a systematic approach to access control within the Air Force enterprise, DOD interest groups and coalition partners. The architecture leverages COTS products that separate the administration of access control from its use of access to data and resources. A prototype was implemented using the enclave model that allows for extensibility. The results from a pilot implementation support the use of Use Case Based Access Control to facilitate security administration and review for the Air Force. The use case based approach provides the sophistication of the attribute based access control with the simplicity of the group based access control.