Starfleet Command is the central organizational and command division of Starfleet. It is based in San Francisco in a vast compound of buildings and facilities called Starfleet Headquarters . Most of Starfleet Command is made up of the Office of the Admiralty and its support staff.
Starfleet Command is headed by the Starfleet Commander-in-Chief, the highest position a Starfleet officer can attain within the space-faring institution, who is responsible for the entire organization and who him/herself answers only to the President of the United Federation of Planets.
The Admiralty assigned to Starfleet's largest operational or field division, Vanguard Command, is also part of Starfleet Command. As of its establishment in 2385, there are sixteen (16) senior Starfleet officers in Vanguard Command that hold the rank of Rear Admiral (lower grade) and above. The Flag Officer-in-Command of Vanguard Command himself, Maximus Hunter, possesses the same rank as the Commander-in-Chief, Edward Jellico.