The undercover campaign of the Special Operations Executive in the Balkans during World War II was of great significance to the Allies. The campaign involved constant movement and activity, severe hardship and privation, and ever-present danger from the Axis troops as the SOE established relations with partisan forces and sought to establish control of a complex and vital theatre of war. This insider’s description of the SOE’s foundation and structure is coupled with accounts of many of its wartime missions.