A policy system shifts the focus from configuring individual devices to managing a network in aggregate, and controlling device behavior through network policies. The system developed within this project is implemented by centralizing control functions into a single software application. At the center of such a policy system is the policy rule. Policy rules may be general and abstract or specific and concrete. In either case, policy rules represent a pairing of conditions and actions that are intended to be device and vendor independent. The composition of policy rules, along with some of the characteristics of devices that are being controlled by policy rules are also modeled. Other characteristics of devices, used to capture the semantics and relationships between different objects being managed, define how the conditions and actions represented in a Policy rule are interpreted and what effect they have on the functions of the device. This project also defines a context for the schema and semantic definitions.