The series consists of records of the Directorate of Military Intelligence as established in 1939, together with some inherited from the former Directorate of Military Operations and Intelligence.

Additional sections were formed during the course of the Second World War, dealing with subjects including publicity and propaganda, prisoners of war, scientific and technical matters, censorship, air photography, anti-aircraft intelligence and military attaches. (Some of these sections had existed during the latter stages of the Great War and for a short period thereafter, but had been disbanded when their work ceased to be necessary). The series includes files on individual prisoners of war, both Allied and enemy, and on prominent Nazis.

There is also medical, historical, and military information about countries which were - or might have been - involved in hostilities.

Information on the organisation of the Directorate of Military Intelligence in World War II can be found in WO 208/5568.