The California Army National Guard (CA ARNG) is one of three components of the California National Guard, a reserve of the United States Army, and part of the National Guard of the United States. The California Army National Guard is composed of 18,450 soldiers. Nationwide, the Army National Guard comprises approximately one half of the US Army's available combat forces and approximately one third of its support organization. National coordination of various state National Guard units are maintained through the National Guard Bureau.