The Secret Intelligence Service (SIS), commonly known as MI6, is the foreign intelligence service of the United Kingdom, tasked mainly with the covert overseas collection and analysis of human intelligence on foreign nationals in support of its Five Eyes partners. SIS is one of the British intelligence agencies and the Chief of the Secret Intelligence Service ("C") is directly accountable to the Foreign Secretary.
SIS Building, the headquarters of MI6 in London
54 Broadway, SIS headquarters from 1924 until 1964
A young Englishman, member of the Secret Intelligence Service, in Yatung, Tibet, photographed by Ernst Schäfer in 1939
Operation Gold: the Berlin tunnel in 1956
The Five Eyes (FVEY) is an Anglosphere intelligence alliance comprising Australia, Canada, New Zealand, the United Kingdom, and the United States. These countries are parties to the multilateral UK-USA Agreement, a treaty for joint cooperation in signals intelligence. Informally, Five Eyes can refer to the group of intelligence agencies of these countries.
NSA Headquarters, Fort Meade, Maryland, United States
ASIO central office, Canberra, Australia
GCHQ, Cheltenham, Gloucestershire, United Kingdom
CSE Headquarters, Ottawa, Ontario, Canada