The man ultimately in charge of RAF missing research was the Air Member for Personnel, the AMP, the equivalent of the Army’s Adjutant-General. Beneath him came the Directorate of Personal Services, the DPS, and beneath this came the Air Ministry Casualty Branch, whose Missing Research and Enquiry Service, the MRES, operated in the field after the liberation of Europe. It was the MRES which, in liaison with the Army Directorate of Graves Registration and Enquiries, conducted all the post-liberation and post-war fieldwork of identifying the RAF missing in Europe.

At the outset of the war in September 1939, the resources devoted to missing research had been inadequate to deal with what soon proved to be the rapidly escalating nature of RAF losses. Thereafter, resources were increased in response to a series of crisis points when existing staff could no longer cope with the heavy workload.

The changes in name and structure can be briefly summarised as follows. At the beginning of the war, the Air Ministry Casualty Branch was known by the departmental name of S.7 (Cas). Its resources were almost immediately discovered to be too small. It was re-designated P.4 (Cas) and increased in size, but the burden of work was so immense that, in January 1942, the Missing Research Section (MRS) of the Casualty Branch was formed to deal with this specific aspect of RAF casualties.

The MRS was confined to offices in Britain until after the invasion of Italy in September 1943 and of France in June 1944. Under its new name, the Missing Research and Enquiry Service, the MRES worked in the field in newly liberated Europe.

Lastly, there was a massive increase in MRES resources in the summer of 1945 when it became obvious that this was the only way that the search would be completed within a reasonable timescale.

The MRES units were never intended to be permanent, and they gradually closed down as their task was accomplished. The last one was disbanded in September 1949 at the same time as MRES HQ.

A considerably smaller unit was then set up, the RAF Graves Service, which was comparatively short-lived, leaving by the end of 1950 only two Missing Research Officers on the Continent to follow up on various outstanding cases. These officers were Flight Lieutenant Hughes in Berlin and Flight Lieutenant Massé, who had a dual role as Liaison Officer working with the Americans at Liège and the Imperial War Graves Commission at Arras.