(UK GOVERNMENT) also spelled MI6; the Secret
Intelligence Service. Under the control of the Home Secretary, along with MI-5 and General
Communications Headquarters (GCHQ).
There is no simple division of labor between the two agencies; MI-5 usually is involved with domestic operations, and MI-6 is usually involved in overseas operations, but the real distinction is that one houses one group of agencies, and the other houses another. Like MI-5, the SIS/MI-6 was founded in 1909 as a joint operation between the Admiralty and the War Office.
During the Cold War, the agency was badly compromised by pro-Soviet staff (the "Cambridge Spy Ring"). It later recovered from Soviet
penetration and recruited Col. Oleg Penkovsky.