His Majesty's Naval Service is the United Kingdom's naval warfare and maritime service. It consists of the Royal Navy, Royal Marines, Royal Fleet Auxiliary, Royal Naval Reserve, Royal Marines Reserve and Naval Careers Service. The Naval Service as a whole falls under the command of the Navy Board, which is headed by the First Sea Lord. This position is currently held by Admiral Sir Ben Key. The Defence Council delegates administration of the Naval Service to the Admiralty Board, chaired by the Secretary of State for Defence.

The Royal Marines Band Service is the musical wing of the Royal Navy and an independent element of the Royal Marines. It currently consists of five bands plus a training wing – the Royal Marines School of Music at HMS Nelson – and its headquarters is at HMS Excellent, Whale Island, Portsmouth.