As American withdrawal from South Vietnam proceeded, increasing concern arose over the enemy's strength in the sanctuaries inside of nominally neutral Cambodia. Officially called the Sanctuary Offensive, eight major U.S. Army and South Vietnamese operations took place in Cambodia between May 1 and June 30, 1970, intending to cut enemy lines of communication, seizing the sanctuary areas and capturing the shadowy COSVN (Central office of South Vietnam). This book is a short history of that campaign and a memoir of an officer who participated.