MI5 - Security Service



Association of Chief Police Officers. ACPO coordinates policing policies on behalf of 43 forces across England and Wales. It liaises with Government on dealing with civil emergencies and terrorist incidents. The National Counter Terrorism Security Office (NaCTSO) works to ACPO and provides a co-ordinating role for the police service in regard to counter-terrorism and protective security.


Anti-Terrorism Crime and Security Act 2001. Parliament passed the ATCSA in December 2001 in response to the heightened threat of terrorist attacks in the UK in the wake of 11 September 2001. The Act includes a range of measures designed to increase the effectiveness of the authorities in combating those directly involved in, or supporting, terrorism. (See: Anti-terrorist legislation).

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Terrorist organisation founded by Usama bin Laden. Al Qaida is also used as an umbrella term to cover a number of groups who broadly support Usama bin Laden's aims and are willing to engage in terrorist attacks to further these aims. (See: Al Qaida and other terrorist groups).


Department for Business Innovation and Skills. BIS aims to assist UK businesses at home and abroad. Its Export Control Organisation handles applications for licences to export controlled military and dual-use technology from the UK and therefore helps to prevent the proliferation of WMD to countries of concern.


Intrusive surveillance whereby an eavesdropping device is installed in a target's home or car. There is a strict regime governing the use of this investigative technique. (See: intrusive surveillance).


The means of ensuring that the essential functions of a business survive a terrorist or other incident, such as natural disaster.

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Chemical, Biological, Radiological and Nuclear. CBRN materials can be used in terrorist attacks or in military weapons under state programmes.


Communications Electronics Security Group. CESG is the Information Assurance arm of GCHQ which provides advice and assistance on the security of communications and electronic data. It works with Government departments and agencies and the Armed Forces, as well as public and private sector companies.


Covert Human Intelligence Source (agent). An important source of secret intelligence. Agent operations are run by specially trained officers and can continue for long periods. (See: Covert Human Intelligence Source).


Continuity Irish Republican Army. (See Irish Republican terrorist groups).


Critical National Infrastructure. Those assets, services or systems that support the economic, political and social life of the UK whose importance is such that any loss or compromise would have life-threatening, serious economic or other grave social consequences for the community, or would be of immediate concern to the Government.


Conter-terrorism (including protective security) is the principle activity of the Security Service. (See Counter-terrorism). 


Centre for the Protection of National Infrastructure Link to external website. An organisation formed from the merger of the National Infrastructure Security Co-ordination Centre (NISCC) and the National Security Advice Centre (NSAC). CPNI, which was launched on 1 February 2007, is responsible for providing integrated security advice to the businesses and organisations which make up the national infrastructure.


Criminal Records Bureau (see Disclosure and Barring Service).


Counter Terrorist Security Advisors (see NaCTSO).

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Director and Co-ordinator of Intelligence (Senior Security Service Officer in Northern Ireland).


See RDD.


Defence Intelligence Staff (see MOD).


The Disclosure and Barring Service (DBS) helps employers make safer recruitment decisions. It also prevents unsuitable people from working with vulnerable groups, including children, through its criminal record checking and barring functions.


Data Protection Act 1998. The DPA gives individuals the right to apply for access to personal data relating to them held by public and private sector organisations. The Act contains a provision for certain exemptions from compliance with all or some of the principles and requirements, for example for the safeguarding of national security. (See Intelligence work and access to information).

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