In this paper, we describe a framework for a refinement scheme located in a centralized policy server that consists of three components: a knowledge database, a refinement rule set, and a policy repository. The refinement process includes two successive steps: policy transformation and policy composition. Our refinement scheme takes policies written in our logic-based abstract policy language as input and generates low level rules directly implementable by individual enforcement points. We provide concrete policy examples in a coalition scenario that forms a mobile ad hoc network (MANET). We demonstrate policy composition using a distributed firewall scheme named ROFL (ROuting as the Firewall Layer) and access control list as enforcement mechanisms. © 2011 IEEE.