MI6

The Secret Intelligence Service (SIS) is responsible for supplying the British Government with foreign intelligence. It is frequently referred to in the mass media and popular parlance by the name MI6, a name used as a flag of convenience during the Second World War when it was known by many names. Alongside the internal Security Service (MI5), the Government Communications Headquarters (GCHQ) and the Defence Intelligence Staff (DIS), it operates under the formal direction of the Joint Intelligence Committee (JIC). SIS is referred to colloquially within the Civil Service as Box 850, after its old MI6 post office box number. Its existence, or indeed that of its sister organisations, was not officially acknowledged in public until 1994. Its headquarters, since 1995, are at Vauxhall Cross on the South Bank of the Thames.