The National Archives makes Denmark's largest collection of questionnaire-based research data available to researchers and students. Order quantitative research data, conduct analyzes online and access register data and international survey data. Formerly known as the Danish Data Archive (DDA), it was the national social science data archive.
Access to the datasets via order. DDA is a member of CESSDA ERIC - an organisation for European social science data archives - which co-operates on EU-projects, agreements on access to holdings in national data archives etc. DDA is active in the Data Documentation Initiative - an international co-operation to define standards for the documentation of metadata. DDA has a member on the steering committee and is involved in the development of software tools for implementing the DDI standard.