The Council Archives' mission is to collect, describe and preserve document files related to the activities of the European Council and the Council of the European Union in order to guarantee their accessibility.

Under EU law, archives more than 30 years old are open to public access. They can be consulted in the Historical Archives Service and are usually on microfiche.

The HAEU preserves and makes accessible for research the archives deposited by EU institutions according to the thirty-year rule governing access to archival material. It also collects and preserves private papers of individuals, movements and international organisations involved in European integration.

The European Parliament Archives Unit manages and preserves Parliament’s official documents and other archival material dating back to 1952, including the deposited documents of individual Members.

The Archives Portal Europe provides access to information on archival material from different European countries as well as information on archival institutions throughout the continent.

The AEI is an electronic repository and archive for research materials on the topic of European integration and unification. The AEI collects two types of materials: certain types of independently-produced research materials and official European Community/European Union documents. Many documents from the Barbara Sloan European Union Delegation Collection (BSEUDC) have been added to the AEI.