The Marine Raider Regiment, formerly known as the Marine Special Operations Regiment (MSOR) is named in commemoration of their elite World War II predecessors, the Marine Raiders. The modern Raiders are a special operations force of the United States Marine Corps. The Regiment's organization was finalized in 2007 and contains three battalions, the First, Second, and Third Raider Battalions. The Marine Raider Regiment is the principal combat component of the Marine Corps Special Operations Command (MARSOC).