The Catalogue Service for the Web (CSW) defines common interfaces to discover, browse, and query meta-data about data, services and other geo-resources. Catalogue services consume and deliver meta-data according to the ISO standards for meta-data. This includes the ISO 19115:2003 Geographic information– Meta-data, which defines the schema for the identification, extent, quality, spatial and temporal schema, spatial reference, and distribution of spatial data; and also ISO 19119:2005 Geographic information–Services, which defines service metadata in terms of the architecture patterns for service interfaces used and defines the standard relationship to the Open Systems Environment model. The ISO 19119 standard also presents a taxonomy for services and prescribes how to create a platform-neutral service specification.