The Maclean Mission (MACMIS) was a World War II British mission to Yugoslav partisans HQ and Marshall Tito organised by the Special Operations Executive (SOE) in September 1943. Its aim was to assess the value of the partisans contribution to the Allied cause and the means to increase it. It was led by a recently promoted Brigadier Fitzroy Maclean and was first such mission with full authorization and a personal message from Winston Churchill. His memoir of these years forms the final third of Eastern Approaches (1949).