In recent years, compnaies and government agencies have come to realise that the data they represent is a significant corporate resource, whose cost calls for rigourous management. With this realisation has come the recognition of the importance of integrating the data that have traditionally only been available from disparate sources. An important component of this integration is the mangement of the metadata that describe, catalogue and provide access to the various forms of underlying business data. This book provides not only a conceptual model of such a metadata respository, but also an enterprise data model of the information technology industry itself.