The Marine Corps characterises itself as a crisis response expeditionary force which is task organised and able to conduct operations across the entire spectrum of military operations. The Corps is a "middleweight force" that is designed to fill the void in our Nation's defence structure between light Special Operations Forces (SOF) and heavier conventional units. A number of decisions pertaining to national security strategy, force structure, and declining defence budgets have resulted in a draw-down of the active Marine Corps. This book examines the draw-down of the Marine Corps, as well as the force structure initiatives, roles and missions, and the restructuring of the Marine Corps.