UNSC High Command, often abbreviated as HIGHCOM, is the highest operational command of the United Nations Space Command and is ultimately in charge of all personnel, equipment, and facilities used by the United Nations Space Command Defense Force.
It was sometimes erroneously referred to as “the Admiralty”, which was a misnomer as its staff was composed of personnel from all branches, not just the Navy.
It was split into two commands: the Unified Ground Command, coordinating all UNSC ground forces, and the UNSC Naval Command, in charge of the Navy. It exercises local authority through regional CENTCOMs, which have responsibility over certain areas of space.
With Top-level brass from every branch forming the UNSC Security Committee, HIGHCOM has directed the strategy for the actions of the UNSC since its very beginning. From combating rebel forces, such as the Eridanus Rebels, to the genocidal war waged by the Covenant, HIGHCOM has been the source of all strategy and information about war.
After the fall of Reach, the headquarters was relocated to the HIGHCOM Facility Bravo-6 in Sydney.

As of 3 March 2558, known members of the committee included the following:

Chairman: Fleet Admiral Sir Terrence Hood, Chief of Naval Operations
UNSC Army liaison: Major General Nicolas Strauss
Office of Naval Intelligence liaison: Admiral Serin Osman
UNSC Marine Corps liaison: General Hogan
UNSC Air Force liaison: General Dellert
UNSC SPARTAN Branch liaison: S-001

UNSC High Command notable locations;
HIGHCOM Facility Bravo-6
HIGHCOM Armory Omega

Despite the Team being small due to “retirement” members have the majority of the following games while I have the entire list.

Xbox 360:
Halo Wars
Halo Reach
Halo CE Anniversary
Halo 3 - ODST
Halo 3
Halo Spartan Assault
Halo 4

Xbox One:
Halo Reach
Halo MCC
Halo 5 - Guardians

Send Anomalous Ideal a message if interested, if not happy hunting Spartans.