From 1782 until 1909, British intelligence at the government level was handled directly by the
Foreign Office, with the Army and Navy also maintaining their own intelligence branches. By 1909, growing tensions with Germany led the
Committee of Imperial Defence to recommend the creation of the
Secret Service Bureau to provide organization and leadership to the intelligence-gathering process as well as a layer of insulation from espionage activities for the Foreign Office. A 10 August 1909 letter from the Director of Naval Intelligence,
Alexander Bethell, to then-Commander
Mansfield Smith-Cumming offered him a "new billet": the opportunity to head the Foreign Section of the new
Secret Service Bureau. Cumming was to begin in this role on 1 October 1909, but bureaucratic and funding obstacles delayed the start of his work. His first full day in this capacity was not until 7 October, and even then, he "went to the office and remained all day, but saw no one, nor was there anything to do there." Cumming's tenure as chief established many of the traditions and trappings of the office. Among the best known of these, he signed documents with the initial "C" in green ink, a custom upheld throughout the history of the service. One tradition that was not maintained was the selection of the Chief from the ranks of the Royal Navy. Although Cumming and his successor
Hugh Sinclair both had long Navy careers, in 1939 Army veteran
Stewart Menzies was appointed over naval officer (and
Churchill's preferred candidate)
Gerard Muirhead-Gould. Plans to rotate the selection of Chief among the various branches of military service were considered, but most subsequent Chiefs have been career intelligence officers. the role's reality was an open secret for many years. In 1932,
Compton MacKenzie was fined under the
Official Secrets Act for elements of his book
Greek Memories. Among these offences, according to
Attorney General Sir
Thomas Inskip was "reveal[ing] the mysterious consonant by which the Chief of the Secret Service is known." By 30 May 1968, however,
The Times was willing to name Menzies as the "former Head of the Secret Intelligence Service" in his obituary. The 1994
Intelligence Services Act established a statutory basis for the Secret Intelligence Service and the position of Chief. Since then, the office has had more public visibility, including a speech by
John Sawers in 2010, described by
The Times as "the first of its kind". The Chief remains the only member of the Secret Intelligence Service whose identity is officially made public. In June 2025, it was announced that Sir Richard Moore would be succeeded by
Blaise Metreweli, who would be the first woman to hold the role of C. ==List of chiefs==