The Secret Intelligence (SI) branch of OSS, an original part of the Coordinator of Information (COI), was to obtain “by secret means information which cannot otherwise be secured and which is not elsewhere available.” In practice, this meant intelligence collection performed by agents, known as human intelligence (HUMINT) today. Although not as well known as the direct-action SO elements in OSS, SI agents faced incredible danger. Small SI teams gathered information by espionage. They established ‘nets’ of local informants or spies to collect specific information, such as enemy military unit locations.
SI personnel operated alone or in two to four person teams in enemy-controlled and neutral countries. They were particularly active in France, Portugal, Spain, Sweden, Switzerland, Turkey, and French Indo-China (now Vietnam). Twenty-nine SI teams under the SUSSEX program were sent into occupied-France. Only three of the SUSSEX teams—COLERE, FILAN, and SALAUD—were captured and executed by the Germans. Forty-one agents under the PROUST program went into occupied France; they only lost one person. One of the most remarkable SI successes was achieved by Allen W. Dulles, who later directed the Central Intelligence Agency (CIA). On 2 May 1945, he arranged the separate surrender of German forces in Italy. Although this occurred just six days before the surrender of Germany, Dulles’ effort saved many Allied lives.