The Historical Archives consist of about 70,000 pre-war and wartime files (1919-1947), 200,000 post-war files (1948-1978), together with a number of special collections, including the ILO Directors and Directors-General Archives - Albert Thomas (1920-1932), Harold Butler (1932-1938), John G. Winant (1939-1941), Edward Phelan (1941-1948), David A. Morse (1948-1970) and C. Wilfred Jenks (1970-1973); C. Wilfred Jenks’ private papers (1920-1973); the records of the International Labour Office (Basel, 1890-1919) and photographic and audiovisual collections.
The ILO maintains also a library with a database.