The PolicyUpdater 1 system is a generic access control system that provides policy evaluations and dynamic policy updates. These functions are achieved by the use of a logic-based language to represent access control policies. In this paper, we discuss the underlying details of the PolicyUpdater system as well as the issues arising from its application to a web server access control system. Integrating the PolicyUpdater system with a web server provides a more flexible and expressive means of representing authorisation policies