deegree Catalogue Service (CSW) is an open source implementation of the OpenGIS® Catalogue Service Web Implementation Specifications. It provides HTTP/SOAP interfaces for searching, accessing, harvesting and manipulating metadata for geographic data and services. Metadata can be searched by their title, topic, date etc. and the spatial extent of the described data/service. deegree supports Dublin Core and ISO 19115/19119/19139 metadata encoding. If the ISO metadata format is used data metadata and service metadata can be coupled. This enables a user to first search for data metadata matching, for example, a specific topic and area and than finding a WMS or WFS serving the data described by the data metadata sets matching the initial search.

The OGC CSW specification is available in different versions. deegree catalogueService supports versions 2.0.0, 2.0.1 and 2.0.2. For CSW 2.0.2 OGC has specified an application profile for ISO metadata (OGC ISO Application Profile for CSW 2.0.2 Specification) which is also supported by deegree CSW. Another important topic covers the INSPIRE specifications for metadata and discovery services. This is supported as far as specifications are completed. There are no compliance tests made available for CSW by the OGC, yet.

deegree catalogueService comes with support for Oracle und PostGIS database backend. An object relational mapping is used to store metadata in a relational database schema. deegree also offers a catalogueManager (aka tibesti) to create, edit, update and manage metadata directly on top of a database backend (to SVN.)