More than forty nations provided assistance to the Republic of Vietnam in its struggle against North Vietnam. This aid ranged from economic and technical assistance to educational and humanitarian contributions. Hundreds of Free World civilians worked in Vietnam as doctors, teachers, and technical specialists. Eight nations also provided military assistance. The flags of these Free World countries-the United States, the Republic of Korea, Thailand, Australia, New Zealand, the Philippines, the Republic of China, and Spain-flew alongside the colors of the Republic of Vietnam at the headquarters of the Free World Military Assistance Forces in Saigon. The military contributions of these nations included combat troops, army medical teams, and individual political warfare advisers. The degree of assistance and co-operation among the concerned Free World nations resulted from years of work and involvement. While many nations expressed sympathy for the plight of South Vietnam, aid did not always come easily, quickly, or to the extent desired. Many nations, beset by their own internal economic and political problems, could do little to help; others did nothing. The story of the efforts of the contributing nations and the efforts to enlist their aid is the subject of this monograph.