A policy engine in a policy-based, outsourced, network management system. In one embodiment, the management system is multi-layered, modular and stores device configuration data in non-device specific format, which are subsequently translated to device-specific format by lower layers of the management system. The non-device specific format is the same (e.g., XML) as that used to create the policies with the user GUI (e.g., browser) and transport them to the service center over the internet. A database stores a policy directory in a hierarchical format that is separate from a policy store (configuration store) for devices in a flat (non-hierarchical or parallel) format. In one embodiment, a policy engine develops policies in a hierarchical format, but then stores the device schema, or objects, in a low-level, flat database. Multiple hierarchical services which impact a single device have the characteristics related to that device knitted together, and then fed back to a policy store database as a flat file for that device, in a non-device specific format. Thus, instead of storing the policies separately, and in hierarchical linked format, the device descriptions are stored with the aspects of all policies that affect that device.