The Ch/Co/Cr-classes were the last of Britain's War Emergency Programme utility destroyers (known as the 12th, 13th, and 14th Flotillas respectively). They were virtually identical to the preceding Z/Ca-class but featured a new Mk. VI HA/LA director as well as remote power control (RPC) for the 4.5-in QF Mk. IV guns. The inclusion of the RPC required the removal of one of the quadruple torpedo tubes but aside from this, armament remained somewhat similar to their predecessors: all ships featured a pair of Bofors anti-aircraft guns in biaxial or triaxial mounts and various combinations of 20-mm guns and/or 2-pdr pompons. The amount of depth charges was also reduced somewhat, to a maximum of 108. Just one of the ships from these three classes (HMS Comet) was commissioned before the end of World War II but many were active during the Korean War and some received modest refits (far less extensive than in the Ca-class) which included the addition of Squid ASW mortar launchers at the expense of the 'X' turret. All Royal Navy ships were paid off by the early 1960s and the Norwegian ships a few years later, but some of the Pakistani transfers were active until the 1980s, making them the longest serving of the War Emergency Class destroyers in any navy. One Canadian ship, HMCS Crescent was later rebuilt as an anti-submarine frigate similar to the Type 15 conversions.

None of the ships from these three classes saw action in World War II but a few were in service during the Korean War (including the battles around the Pusan Perimeter), the Malayan Emergency as well as the Suez Crisis. HMS Consort and HMS Concord were involved in the Yangtze Incident during the Chinese Civil War, the former suffering numerous casualties. Only one of the ships was lost in combat: the Pakistani Shah Jahan was hit by SS-N-2 Styx missiles fired from Indian missile boats during the 1971 Indo-Pakistani War and damaged beyond repair.