The commanding officer (CO) is the officer in command of a military unit. Typically, the commanding officer has ultimate authority over the unit, and is usually given wide latitude to run the unit as he sees fit, within the bounds of military law. In this respect, commanding officers have significant responsibilities (for example, the use of force, finances, equipment, the Geneva Conventions), duties (to higher authority, mission effectiveness, duty of care to personnel) and powers (for example, discipline and punishment of personnel within certain limits of military law).
In some countries, commanding officers may be of any commissioned rank; usually there are more officers than command positions available, and time spent in command is generally a key aspect of promotion, so the role of commanding officer is highly valued, and in theory only goes to the best officers. The commanding officer is often assisted by an Executive Officer (XO) or Second-in-Command (2i/c), who handles personnel and day-to-day matters. Larger units may also have staff officers of various responsibilities.
In the British Army
, Royal Marines
, and many other Commonwealth
military and paramilitary
organisations, the title of commanding officer is reserved for commanders of major units (regiments
and similar sized units), almost invariably holding the rank of Lieutenant Colonel
and usually referred to within the unit simply as "the Colonel". The post of a commander of a minor unit (company
) is collectivelly referred to as the Officer Commanding
(OC). More specifically they are referred to as the Company Commander, Squadron Leader, etc. Officers and NCOs in charge of platoons
are just referred to as Commanders (Platoon Commander, Troop Leader, Section Commander/Leader, etc).
In the Royal Air Force
, the title of Commanding Officer is reserved for Station
Commanders or commanders of independent units.
In the Royal Navy
, Commanding Officer is the official title of the commander of any ship, unit or installation. However, they are referred to as "the Captain" no matter what their actual rank, or informally as "Skipper"
or even "Boss".
In the United States
, the status of commanding officer is duly applied to all commissioned officers who hold lawful command over a military unit, ship, or installation.
The commanding officer of a company
is referred to as a Company Commander
, the commanding officer of a battalion
is referred to as a Battalion Commander
, and the commanding officer of a brigade
is referred to as a Brigade Commander
. At the division
level and higher, however, the commanding officer is referred to as the Commanding General
, as these officers are normally of general
In the United States Air Force
, the commanding officer of a unit is similarly referred to as the unit commander, such as squadron
commander, group commander, wing commander, and so forth.
In the United States Navy
, commanding officer is the official title of the commander of a ship, but they are usually referred to as "the Captain" regardless of their actual rank, or informally referred to as "Skipper"