The Command Officer's Test is an advanced Starfleet exam given to starship crewmembers who have, after passing their Bridge Officer's Test, established themselves as competent bridge officers. Passing the Command Officer's Test allows a crewmember to serve as a commanding officer in their own right, while an officer who has only passed the Bridge Officer's Test can only take command when the other officers typically in command are unavailable. A Command Officer Certification is awarded to all officers who pass the exam, and the names of the officers who pass the exam and are of the rank of Commander are added to the Starfleet command registry, which puts them in line for their own command. (Star Trek: Remington)