In Britain, the function and nature of the police has been carefully defined to create a distinct, decentralized and normally unarmed civilian police system, which is unlike the military and national police systems found elsewhere in Europe. In recent years, major public order problems and the growth of armed and organized crime as well as terrorism have precipitated the creation of permanent special emergency units and reserves in addition to the ordinary divisional police. It has also been necessary to expand the role of the police intelligence service, the Special Branch. These developments have raised fears that a 'third force' in the form of paramilitary police might be evolving, and fears have also been expressed about the police surveillance of various political and protest groups. Additional British police responsibilities have arisen from 1974 and 1976 parliamentary terrorism control acts as well as from international conventions on terrorism. Valid questions concerning civil liberties have been raised about the activities of the Special Branch and its criteria for the collection of intelligence information. The British ordinary police are required to protect the public by preventing terrorist acts and conducting counter-terrorist operations. They guard buildings, protect persons, support divisional or regional police forces and are the principal source of expertise and manpower in antiterrorist operations. Although specialist antiterrorist police units have diluted the traditional form of unarmed policing, Britain has not compromised the reputation of its police as a civil force serving the community. Forty-seven footnotes are provided.