The SIS

John Scarlett 2004–present
Sir Richard Dearlove 1999–2004
Sir David Spedding 1994–1999
Sir Colin McColl 1989–1994
Sir Christopher Curwen 1985–1989

The Secret Intelligence Service (SIS), more commonly known as MI6 (originally Military Intelligence Section 6), or the Secret Service or simply Six, is the United Kingdom's external security agency. Insiders sometimes refer to it as box 850 which comes from its old postal box number.

SIS is responsible for the United Kingdom's espionage activities overseas, as opposed to MI5 which is charged with internal security within the UK. It was founded in October 1909 (along with MI5) as the Foreign Section of the Secret Service Bureau. Its first director was Captain Sir George Mansfield Smith-Cumming, who, often dropping the "Smith", used his initial "C" as a code name which was also used by all subsequent directors of SIS (compare with "M" in Ian Fleming's James Bond novels).

The Intelligence Services Act 1994 (SW9311) defines the role of MI6 as:

"(a) to obtain and provide information relating to the actions or intentions of persons outside the British Islands; and (b) to perform other tasks relating to the actions or intentions of such persons...[in relation to] the interests of national security, with particular reference to defence and foreign policies...the interests of the economic well-being of the UK...or in support of the prevention or detection of serious crime."

The SIS Headquarters

In 1909, a parliamentary study found evidence of widespread German infiltration, and noted that there was "no organization…for accurately identifying its extent and objectives." As a result, the British government established the Secret Service Bureau. The bureau was divided into a Home Section under Captain Mansfield Cumming, and a Foreign Section directed by Captain Vernon Kell. The two came to be known, respectively, as "C" and "K." After World War I broke out, the Foreign Section became MI1(c), and in 1921 the Secret Intelligence Service (SIS), or MI6. Directors of SIS have thenceforth been known by the designation "C" after Cumming, who remained the head of SIS/MI6 until 1923. (The "K" designation, on the other hand, seems to have ended with Kell, first director-general of MI5.)