The Security Service MI5

The Security Service, also MI5 (Military Intelligence, Section 5), is the Uk's national counterintelligence and security agency and is part of its intelligence system alongside the Secret Intelligence Service (MI6), Government Communications Headquarters (GCHQ) and Defence Intelligence (DI). The service is directed to shield economical interests and British parliamentary democracy, and counter espionage and terrorism within great britain.



Within the civil service community the service is colloquially called Box 500 (after its official wartime address of PO Box 500; its present address is PO Box 3255, London SW1P 1AE).

The service has had a national headquarters at Thames House in London since 1995 on Millbank, drawing together staff from several places into one HQ facility. The service has offices across the UK including an HQ in Northern Ireland.

The company who constructed it shown aspects of the northern operations center in Greater Manchester. Strategies to start the northern procedures center were reported by The Manchester Evening News in February 2005,[6] and plans to start a long-term office that was Scottish were reported by The Scotsman in January of that year.