RM Stonehouse is the base Unit at Royal Marines Barracks Stonehouse. The Unit strength is approximately 120 service personnel, which includes a few members of the Royal Navy and are supported by 50 civilian staff. The Unit tasks are to maintain a high level of security for the Barracks and to provide administrative support for all resident Units within the Barracks. In order to achieve its aims the Unit has several different departments.

Medical and Dental services are provided within the Barracks and the OC Base Squadron Dept has the capacity to deal with clothing, transport, weapons and general stores. The Unit has its own Imprest, Movements and records Dept and the Main Galley is run by 2i/c Base Squadron. RM Stonehouse has a comprehensive Education and Resettlement Centre and a dedicated Military Guard Provost Service to guard the establishment.

Stonehouse is also the location of the RN/RM Sailing Centre located at the Camber overlooking Drake Island and Plymouth Sound. The centre provides dinghy, yachting and powerboat training as well as racing and Adventurous Training.