We work very closely with both the Secret Intelligence Service (SIS) and the Government Communications Headquarters (GCHQ). We each have different but related functions, and there are many areas where we provide mutual assistance. We collaborate with SIS and GCHQ across all the main functions of our work and there are several joint teams staffed by members of all three agencies.
MI5 works particularly closely with the Home Office and has strong links with the Foreign & Commonwealth Office, the Cabinet Office, the Northern Ireland Office, the Department for Business, Innovation and Skills, and the Ministry of Defence. We also advise all central government departments and agencies on protective security matters.
We work closely with the police
We have a very close working relationship with the national Counter Terrorist Police (CTP) network in Great Britain, the Police Service of Northern Ireland (PSNI), and other national law enforcement agencies including the National Crime Agency and Border Force.
These close partnerships are at the heart of our collective efforts to keep the country safe from all threats to national security. We work collaboratively with these critical partners, sharing and receiving intelligence to assist in many areas of our work. This includes information and intelligence assessments on current threats, and working closely with police partners on investigations to assist their evidential gathering capability, where criminal proceedings can be brought. We are constantly refining how we work together to jointly achieve operational successes in the face of evolving threats and technological change.
We are charged with protecting national security, which may be threatened both in the UK and overseas. We work closely with our counterparts in other countries to ensure the security of UK interests overseas. In an increasingly globalised world, threats to our key partners have an impact on the UK's national security too. In many areas of our work we rely heavily on the support of SIS and the assistance given by foreign security and intelligence services.