The Special Boat Service (SBS) is the special forces unit of the United Kingdom's Royal Navy. The SBS can trace its origins back to the Second World War when the Army Special Boat Section was formed in 1940. After the Second World War, the Royal Marines formed special forces with several name changes—Special Boat Company was adopted in 1951 and re-designated as the Special Boat Squadron in 1974—until on 28 July 1987 when the unit was renamed as the Special Boat Service after assuming responsibility for maritime counter-terrorism. Most of the operations conducted by the SBS are highly classified, and are rarely commented on by the British government or the Ministry of Defence due to their sensitive nature.
The Special Boat Service is the maritime special forces unit of the United Kingdom Special Forces and is described as the sister unit of the British Army 22 Special Air Service Regiment (22 SAS), with both under the operational control of the Director Special Forces. In October 2001, full command of the SBS was transferred from the Royal Marines to the Royal Navy; whilst retaining the green beret. On 18 November 2003, the SBS were given their own cap badge with the motto "By Strength and Guile". This follows opening recruitment from only the Royal Marines to all three services of the British Armed Forces. The SBS has traditionally been manned mostly by Royal Marines Commandos.