CESSDA Vocabulary Service enables users to discover, browse, and download controlled vocabularies in a variety of languages. The service is provided by the Consortium of European Social Science Data Archives (CESSDA). The majority of the source (English) vocabularies included in the service have been created by the DDI Alliance. The Data Documentation Initiative (DDI) is an international standard for describing data produced by surveys and other observational methods in the social, behavioural, economic, and health sciences.