A set of NPCL constraints can be specified using an XML document conforming to the NPCL XML Schema. This representation of the NPCL constraints is separate from the representation of the constraints in a topic map and so does not simply use the XTM syntax. NPCL XML Schema is also a more compact representation of a set of NPCL constraints than the topic map representation and is more easily processed using standard XML tools such as XSLT. This section describes the NPCL XML Schema in detail. The W3C XML Schema representation is also included in the TMCore distribution and can be downloaded from the NetworkedPlanet website.