Over 25 years of guerrilla warfare have made the IRA a major problem for the police and armed forces; for both sides, the gathering of intelligence is vital. Electronic and human surveillance of IRA suspects is conducted constantly by the security forces, as is the use of informants. 

Techniques have been developed by the IRA to combat British Army radio signals by using radar guns and microwave receivers. British intelligence sources have been successful in effecting the seizure of major consignments of arms destined for IRA use, such as that made in October 1971 by Dutch police at Schiphol airport. As a means of defeating airborne surveillance of arms dumps, major IRA arms bunkers are now generally built inside farm buildings or under silage pits. On capture and imprisonment, IRA members demand recognition as prisoners of war (POW) with special category status.