A covert human source, recruited by SIS to provide secret
intelligence or assistance to the Service, who has undergone a
period of assessment and whose reporting to SIS has been validated.
To be distinguished from a member of SIS' staff.
Acronym occasionally used for SIS - British Secret Intelligence
Service to distinguish us from others with similar acronyms - CSIS
(Canadian Security Intelligence Service), ASIS (Australian Secret
Intelligence Service) and NZSIS (New Zealand Security Intelligence
Chief of SIS. Used in honour of the first Chief of SIS, Sir
Mansfield Cumming, who habitually signed himself 'C'.
Central government department with responsibilities for
co-ordinating the UK national intelligence machinery, including the
Joint Intelligence Committee.
Chemical, Biological, Radiological and Nuclear. This acronym
describes weapons types.
SIS intelligence reports as issued to other government
departments (customers). These reports are generally
"single-source", relating to the intelligence provided by one agent
or source. Although the reports may include commentary from SIS and
some estimate of its value to customers, it is not with SIS'
function to analyse its importance or weight. They are composed
according to a set format, providing details of the subject
covered, and the reliability of the source. The acronym originates
from the archaic security marketing 'Exclusive for C'.
Defence Intelligence Staff. Intelligence analytical organisation
of the Ministry of Defence traditionally serving the UK armed
forces but also serving wider government customers.
Foreign and Commonwealth
Office. The UK ministry of foreign affairs, responsible for the
formulation and delivery of foreign policy. The FCO works closely
with SIS overseas. The Foreign Secretary is the Minster responsible
for the Secret Intelligence Service, under the Prime Minister.
Headquarters. The UK sigint (signals intelligence) agency,
based in Cheltenham. One of SIS's two sister intelligence and
security agencies also with the Security Service (MI5).
Her Majesty's Government. An alternative phrase for 'the British
The UK ministry of the interior. The Home Secretary is the
Minister responsible for the Security Service.
"Human intelligence", namely intelligence derived from human
Act of 1998. A key piece of UK legislation to which SIS is
Act of 1994. This act of parliament was the first time
that SIS' function and role were defined in law. It sets out what
the Service may do.
Joint Intelligence Committee. Part of the Cabinet office and the
central body of the national intelligence machinery. It advises on
the priorities for intelligence collection and assesses Agency
performance against those priorities.
Terrorism Analysis Centre. Sits within the Security Service to
analyse all source intelligence on terrorist threats to the UK and
UK interests. Staffed by members of all three intelligence and
security agencies and the DIS, FCO, Home
Office, the Police and other government departments.
Foreign intelligence services with which SIS cooperates. It is
SIS policy not to comment on its relationships with liaison
Commonly used but unofficial title for SIS dating back
to before WWII.
Commonly used but unofficial title for the Security
A member of SIS staff. Often confused in popular vocabulary with
An intelligence gathering operation.
Secrets Act (1989) prohibits the disclosure of sensitive
information relating to security, intelligence, defence and foreign
relations, and applies to all applicants to, and employees of, SIS.
You can read more about the Official Secrets Act at the Office of
Public Sector Information.
Intelligence requirements set by the JIC.
Investigatory Powers Act of 2000. Regulatory Act which
established a Commissioner for Interception, a Commissioner for the
Intelligence Services and the Investigatory Powers
The Secret Intelligence Service, also known as MI6.
The Special Operations Executive. WWII clandestine operations
agency absorbed into SIS towards the end of the war.
Security-edited records from the period before absorption have been
released by SIS to the UK National Archive.
Any source of information or intelligence. An agent may be a
source but a source is not automatically an agent.
Signals intelligence. The primary task of GCHQ.
Information acquired against the wishes and generally without
the knowledge of the originators or possessors. Sources are kept
secret from readers as are the techniques used to acquire the
information. Intelligence provides privileged insights not
Single Intelligence Account. The budget through which all three
intelligence and security agencies are funded.