Sir John Cotesworth Slessor (1897-1979) was one of Great Britain's most influential airmen.He played a significant role in building the World War II Anglo-American air power partnership as an air planner on the Royal Air Force Staff, the British Chiefs of Staff, and the Combined Chiefs of Staff.He coordinated allied strategy in 1940-41, helped create an Anglo-American bomber alliance in 1942, and drafted the compromise at the Casablanca Conference that broke a deadlock in Anglo-American strategic debate.Also, Slessor was instrumental in defeating the U-boat menace as RAF Coastal Commander, and later shared responsibility for directing Allied air operations in the Mediterranean.Few aspects of the allied air effort escaped his influence: pilot training, aircraft procurement, and dissemination of operational intelligence and information all depended to a degree on Slessor.His influence on Anglo-American operational planning paved the way for a level of cooperation and combined action never before undertaken by the military forces of two great nations.