Policy-based systems consist of interacting software artifacts and, at first glance, can be tested as any other software system. In a policy-based system, however, the behavior of system entities may change dynamically and frequently, depending on the policy rules governing this behavior. Therefore, policy-based systems demand for a testing approach that especially allows for the testing of dynamically changing system behavior. Thus, testing of policy rules has to check if the behavior that is actually enforced by a set of policies, conforms to the intended behavior of the corresponding system entities. Scenarios are an important means to specify behavior of software entities. In this paper, we introduce an approach to test policybased systems with scenarios, and present an (embedded) domain-specific language for scenario-based testing.