The DCAT Application Profile for data portals in Europe (DCAT-AP) is a specification based on the Data Catalogue Vocabulary (DCAT) developed by W3C.

This application profile is a specification for metadata records to meet the specific application needs of data portals in Europe while providing semantic interoperability with other applications on the basis of reuse of established controlled vocabularies (e.g. EuroVoc) and mappings to existing metadata vocabularies (e.g. Dublin Core, SDMX, INSPIRE metadata, etc.).

Also, DCAT-AP provides a common specification for describing public sector datasets in Europe to enable the exchange of descriptions of datasets among data portals. DCAT-AP allows:

• Data catalogues to describe their dataset collections using a standardised description, while keeping their own system for documenting and storing them.
• Content aggregators, such as the European Data Portal, to aggregate such descriptions into a single point of access.
• Data consumers to more easily find datasets through a single point of access.

DCAT-AP has an extension GeoDCAT-AP for describing geospatial datasets, dataset series and services. Another extension, StatDCAT-AP, provides specifications and tools that enhance interoperability between descriptions of statistical data sets within the statistical domain and between statistical data and open data portals.

Core Public Service Vocabulary Application Profile (CPSV-AP) is a reusable and extensible data specification used for harmonising the way public services are described in a machine-readable format. CPSV-AP captures fundamental characteristics of a public service, such as the name, description, competent public organisation, output, etc. 

Public administrations and service providers can therefore use this approach to describe their services and guarantee a level of cross-domain and cross-border interoperability at European, national and local level.

Breg DCAT-AP is dedicated to an application profile of DCAT-AP for base registries, aiming to provide a standard data model / specification for base registries access and interconnection.

The Asset Description Metadata Schema (ADMS) is a vocabulary to describe reusable solutions, such as data models and specifications, reference data and open source software. The ADMS specification was originally drafted to describe semantic interoperability solutions (previously referred to as semantic assets).