An aide-de-camp (UKˌeɪddəˈkɒ̃, -ˈkaemp; French expression meaning literally "helper in the [military] camp") is a personal assistant or secretary to a person of high rank, usually a senior military, police or government officer, or to a member of a royal family or a head of state.
An aide-de-camp may participate at ceremonial functions, and the first aide-de-camp is typically the foremost personal aide. This is not to be confused with an adjutant, who is the senior administrator of a military unit.
The badge of office for an aide-de-camp is usually the aiguillette, a braided cord in gold or other colours, worn on the shoulder of a uniform. Whether it is worn on the left or the right shoulder is dictated by protocol.
In some countries, aide-de-camp is considered to be a title of honour, which confers the post-nominal letters ADC, A.D.C. or A de C.
In Argentina, three officers, one from each armed service, of the rank of lieutenant colonel or its equivalent, are appointed as aide-de-camp to the president of the republic and three others to the minister of defense, these six being the only ones to be called edecán, which is one Spanish translation for aide-de-camp (edecán is a phonetic rendition of the French term; ayuda or ayudante de campo is a calque).
A controversy was raised in 2006, when president Néstor Kirchner promoted his army aide-de-camp, Lieutenant Colonel Graham, to colonel, one year ahead of his class. Upon becoming president, Cristina Kirchner decided to have, for the first time, female officers as her aides-de-camp.
In each of the armed forces, the chief of staff and other senior officers have their own adjutants, normally of the rank of major or lieutenant colonel, or its equivalent. At unit level, the unit S1 (personnel officer) doubles as the unit commander's adjutant, although in recent times in many units this practice has been left only for ceremonial purposes, while for everyday duties a senior non-commissioned officer performs the adjutant's activities.