This article is about a military unit. For alternate meanings see Corps (disambiguation).

A corps (a word that immigrated from the French language, pronounced like English "core", but originating in the Latin "corpus, corporis" meaning body; plural same as singular) is a large military unit or formation.

In many armies, it refers to a unit of approximately 30,000 troops, composed of two or more divisions, and typically commanded by a lieutenant general. During World War I and World War II, due to the large scale of combat, multiple corps were combined into armies which then formed into army groups. The Red Army, however, did not use corps. Its corps-sized formations were called armies and its army-sized formations were called fronts.

As of 2003, the United States Army has four field corps. The structure of a field corps is not permanent; many of the units that it commands are allocated to it as needed on an ad hoc basis. On the battlefield, the field corps is the highest level of the forces that is concerned with actually fighting and winning the war. (Higher levels of command are concerned with administration rather than fighting, at least in current doctrine.) The corps provides operational direction for the forces under its command. Corps are designated by consecutive Roman numerals. The present active corps in the US Army are I Corps ("eye core"), III Corps, V Corps, and XVIII Airborne Corps; their numbers derive from four of the 30-odd corps that were formed during World War II. It also refers to a grouping of specialized troops such as the Army Corps of Engineers and the United States Marine Corps.

In the British Army, too, a corps is also a grouping by common function (e.g. Intelligence Corps, Royal Logistic Corps, Royal Corps of Signals), performing much the same function as a ceremonial infantry or cavalry regiment, with its own cap badge, stable belt, and other insignia and traditions. The Royal Armoured Corps and the Corps of Infantry are loose groupings of independent regiments, but do not have their own insignia. There is still a corps headquarters for operational control of forces. I Corps of the British Army of the Rhine was redesignated the Headquarters Allied Command Europe Rapid Reaction Corps in 1994. It is no longer a purely British formation, although the UK is the 'framework nation' and provides most of the staff for the headquarters. A purely national corps headquarters could be quickly reconstituted if necessary. It was last deployed as the headquarters commanding land forces during the Kosovo War in 1999 and also saw service in Bosnia, commanding the initial stages of the IFOR deployment prior to that in 1996. Otherwise, the only time a British corps headquarters has been operationally deployed since 1945 was II Corps during the Suez Crisis.

In the Australian Army a Corps is like but different to the British usage. An Australian Army Corps is a group of troops of like function, ie belonging to the same arm or service, as with the British, however in the Australian Army Corps provide additonal function in that they typically provide special to arm training to memebrs of the Corp, as well as typcially being the authoritive institution for all aspects of the day to day and tactical life of the Corps. For exmaple a soldier leaving recruit training (the standardaised recruit traning all solders undergo - basic in US terms) will then be assigned to Initial Employment Training which is his inital specialist training. This will typically be untderaken at a his Corps School. Later as his career progresses he wil return to his Corps school for futher special to arm specialist traning. The Corp also is the organisation that develops doctrine and tactics for the relevatn arm. Eg Doctrine for Armour, Cavalry or APC units will be developed at the School of Armour, the "headquarter" of the Royal Australian Armoured Corps. Australian Army Corps do have their own distincitive insignia. When a Corp insignia is worn when a solder is posted to a non unit (eg an administirive posting, eg a Military District headquarters or a Recruting Unit) posting, whilst travelling between postings and in units which don;t ahve their own distincitve insignia.

Related topics

• Corps area
• United States Marine Corps
• Eurocorps
• List of corps of the United States Army