|Command Uniform||Aerospace Corps Duty Uniform||Marine Corps Duty Uniform|
Every Starfleet facility has a single commanding officer responsible for the safety of his/her crew and the success of their missions. S/he has final accountability for any actions taken by his/her crew, and Starfleet goes to great lengths to prepare a CO for the job ahead, including the interpretation and execution of Starfleet rules and regulations.
Each Commanding Officer is responsible for building and maintaining a website for their ship; beginning and ending missions; and sending in monthly reports to his or her Task Force CO to keep him informed of the events on his or her ship.
A 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 (2XO), who handles personnel and day-to-day matters. Larger units may also have staff officers of various responsibilities.
In the Starfleet, commanding officer is the official title of the commander of a ship, but they are usually referred to as "Captain" regardless of their actual rank, or informally referred to as "Skipper".
Starfleet Marine Corps
In the Starfleet Marine Corps, the Commanding Officer is the title of the Marine in command of the unit. This can be an officer of any rank, but must be an officer. Since the Marine and Navy Chain of Command is different, on a Starship or Starbase, the Marine CO has full authority over his unit as if he was a Starship Captain, yet is still subject to the authority of the Commanding Officer of the Starship/Starbase.
Starfleet Aerospace Corps
In the Starfleet Aerospace Corps, the title of Commander, Air Group, or more informally referred to as CAG, is given to the individual who is the Commander of the Fighter squadron that is stationed on the starship or starbase. This position can be held by either an Officer or a high-ranking Enlisted personal.