As a consequence of the closure of HMAS Encounter in June 1994, the Navy Support Office South Australia was established in Keswick Barracks, just on the southern outskirts of Adelaide's parklands. The Navy Support Office fulfilled various roles and functions necessary to represent Navy's interests in South Australia.
In 1998, the Navy Support Office was retitled Navy Headquarters South Australia. Navy Headquarters is located in the Headquarters Building at Keswick Barracks.
The major function of Navy Headquarters is to provide administrative support to Navy personnel working in South Australia and to represent Navy in the local community. Navy personnel work at various sites in the Adelaide metropolitan area including the CBD, Keswick Barracks, RAAF Edinburgh, DSTO Salisbury and the ASC site at Osborne.
Navy Headquarters also supports various RANR elements including a Reserve Band, the South Australian Detachment of the Royal Australian Navy Band.