The aim of this chapter, written by C.I. Hamilton, is to better understand the Second World War British Admiralty by looking at it via a small, connected organization, Combined Operations Headquarters (COHQ), and to approach the latter through some of the individuals involved, including not just its two famous heads, Sir Roger Keyes and Lord Louis Mountbatten, but also two important middle-level officers, Wing Commander the Marquis of Casa Maury and Captain R.M. Ellis, who were blamed for much. They lead one to look to administrative factors for explanations, in particular with regard to the take-over of part of COHQ's functions by the Admiralty in 1943. That entails a survey, mainly with relation to the Admiralty, of the administration of operational planning, supply, production, and of administration itself, and then a return to consider the 1943 take-over. It is proposed that with the unprecedented growth of Admiralty bureaucracy during the war, impelled by the development of maritime warfare, many more formal bureaucratic linkages were required, together with more local initiative, and these entailed Admiralty imperialism. The conclusion is that circumstances were primary, not personalities, and that there were implications for postwar defense reform.