MI6

The Secret Intelligence Service (SIS) is the foreign intelligence agency for the United Kingdom. It is most commonly known by the name MI6. The primary mission of the SIS is to collect foreign intelligence to support national interests. This work helps protect the country's security and its economic well-being. Unlike its sister agencies, MI5 and GCHQ, the SIS focuses exclusively on intelligence gathering outside the British Islands.

The agency operates through several specific priority roles. One major task is counter-terrorism, which involves preventing extremism against the UK or its allies. Another role is counter-proliferation, which focuses on stopping the spread of dangerous weapons. The SIS also provides intelligence to support cyber security and digital expertise. By doing this, they help disrupt criminal activities and maintain stability overseas. Their work helps detect violations of international law and prevents hostile influence.

Governance of the SIS is strictly defined by United Kingdom law. The agency falls under the supervision of the Foreign, Commonwealth & Development Office. The Foreign Secretary holds day-to-day ministerial responsibility and appoints the head of the SIS. This leader is known as the Chief of the Secret Intelligence Service, or "C." The Chief has a dual responsibility. Internally, they manage the continuous gathering of intelligence and resource allocation. Externally, the Chief acts as a secret diplomat to maintain vital intelligence alliances.

Command and control involve four main government entities. These include the Central Intelligence Machinery and the Ministerial Committee on the Intelligence Services. The Permanent Secretaries' Committee on the Intelligence Services also plays a role. Finally, the Joint Intelligence Committee (JIC) assesses intelligence from SIS, MI5, and GCHQ. The JIC presents these findings to cabinet ministers to help them create government policies. This process ensures that intelligence analysis informs national security and defense decisions.

The history of the SIS began on October 1, 1909. It started as the Foreign Section of the Secret Service Bureau. This bureau was a joint effort between the Admiralty and the War Office. They wanted to monitor the activities of the Imperial German government. During the First World War, the section became known as MI1(c). Its first director was Captain Sir Mansfield George Smith-Cumming. He famously signed his letters with a green ink "C."

During the inter-war period, the service changed how it operated. In 1919, Cumming created a passport control department to provide diplomatic cover for agents. This allowed operatives to have diplomatic immunity while working abroad. Recruitment during this time was often very casual. Some leaders even preferred agents who did not have university degrees. It was not until the Second World War that the agency began using methodical training for its agents. The name "MI6" became a convenient label during this conflict.

For many years, the existence of the SIS was not officially acknowledged. This changed in 1994 with the Intelligence Services Act (ISA). This law placed the organization on a statutory footing for the first time. It provides the legal basis for all SIS operations. Since 1994, the headquarters have been located in the SIS Building in London.

The agency is now subject to public oversight by the Investigatory Powers Tribunal. It is also watched by the Intelligence and Security Committee of Parliament.

Financial oversight is also a key part of the agency's structure. HM Treasury requires the agencies to prepare annual financial statements. Because of security, the government does not publish these specific statements to the public. However, they are audited by the Comptroller and Auditor General. For the 2021–2022 period, the combined spending for British intelligence services was £3.44 billion. This total included roughly $1.09 billion for staff pay and agents. It also included £636 million for capital spending.