The United Kingdom has three intelligence and security services, collectively known as the Agencies more
Discover more about the Security Service, also known as MI5 - the United Kingdom’s internal intelligence agency more
The Defence Intelligence Staff is the main provider of strategic Defence Intelligence to the Ministry of Defence and the Armed Forces more
Secret Intelligence Service
Find out the history of MI6 and learn more about spies from this period more
Special Branch
The Metropolitan Police Special Irish Branch was formed in March 1883 to gather, collate, analyse and exploit intelligence more
Government Communications Headquarters
Find out how Government Communications Headquarters (GCHQ), helps to keep communication and information systems safe from hackers and other threats more
Joint Intelligence Committee
The origins of the Joint Intelligence Committee (JIC) can be traced back to 1936 more
Related information
Find out which organisations have been involved in intelligence related activities more
In the Bookshop
Enigma Code-Breaking and the Second World War
Let The National Archives ease you into discovering security history more