This paper describes an approach for application specific conflict prevention based on model-driven refinement of policies prior to deployment. Central to the approach is an algorithm for the retrieval of application-specific data from an information model relating to the subject and targets of a given policy. This algorithm facilitates the linkage of policies loosely defined at a high level of abstraction to detailed behavioural constraints specified in the information model. Based on these constraints policies are then modified so that conflicts with other deployed policies can be readily identified using standard policy conflict detection techniques. This approach enables policy enforcement to be cognisant of application specific constraints, thereby resulting in a more trustworthy and dependable policy based management system.