The UK Data Archive (UKDA) is a centre of expertise in data acquisition, preservation, dissemination and promotion and is curator of the largest collection of digital data in the social sciences and humanities in the UK. It is funded by the Economic and Social Research Council (ESRC), the Joint Information Systems Committee (JISC) of the Higher Education Funding Councils and the University of Essex. Founded in 1967, it now houses several thousand datasets of interest to researchers in all sectors and from many different disciplines.

The UKDA is a member of the Council of European Social Science Data Archives (CESSDA), and the International Association of Social Science Information Service and Technology (IASSIST) through which it plays a lead role in international collaborative projects on issues such as data sharing, metadata and social science thesauri. UKDA is also a member institution of the US national social science and historical data archive, Inter-university Consortium for Political and Social Research (ICPSR) in Michigan and the International Federation of Data Organizations (IFDO).

The UKDA provides resource discovery and support for secondary use of quantitative and qualitative data in research, teaching and learning. As a lead partner of the Economic and Social Data Service (ESDS), the UKDA is responsible for:

• overall integration and management of the ESDS
• access and preservation, focusing on the central activities of data acquisition, processing, preservation and dissemination
• ESDS Qualidata, a specialist service for a range of qualitative datasets
• ESDS Longitudinal, undertaken jointly with the Institute for Social and Economic Research (ISER)

• ESDS International, working with Manchester Information and Associated Services (MIMAS), providing access to international micro data
• ESDS Government, working with the Cathie Marsh Centre for Census and Survey Research (CCSR), facilitating access to large-scale government datasets

The UKDA also provides preservation services for other data organisations, supports the National Centre for e-Social Science (NCeSS) and facilitates international data exchange through agreements with other national archives. The UKDA hosts the History Data Service and Census.ac.uk, facilitating access to the census data resources for UK higher and further education.

The UKDA's involvement in Research and Development projects has made a significant contribution to new developments in data preservation and dissemination, metadata standards, software for web browsing, data discovery and data delivery.