Close quarters combat (CQC) is a tactical concept that involves physical confrontation between several combatants. It can take place between military units, police and criminals, and other similar scenarios. In warfare, it usually consists of small units or teams engage the enemy with personal weapons at very short range, up to 100 meters, from proximity hand-to-hand combat to close-quarter target negotiation with short-range firearms. In the typical close quarters combat scenario, the attackers try a very fast, violent takeover of a vehicle or structure controlled by the defenders, who usually have no easy way to withdraw. Because enemies, hostages/civilians, and fellow operators can be closely intermingled, close quarters combat demands a rapid assault and a precise application of lethal force. The operators need great proficiency with their weapons, and the ability to make split-second decisions in order to minimize accidental casualties.
Criminals sometimes use close quarters combat techniques, such as in an armed robbery or jailbreak, but most of the terminology comes from training used to prepare soldiers, police, and other authorities. Therefore, much material relating to close quarters combat is written from the perspective of the authorities who must break into the stronghold where the opposing force (OPFOR) has barricaded itself. Typical examples would be commando operations behind enemy lines and hostage rescues.