U.S. Infantry Squad Composition in the Vietnam War

Squad: the squad leader usually had the rank of staff sergeant, sergeant or corporal, and a squad usually consisted of eight to ten soldiers.

Platoon: usually commanded by a lieutenant and supported by a staff sergeant. Platoon units are commanded by a platoon sergeant, a platoon sergeant, and two or more squad leaders.　Squad: usually commanded by a staff sergeant assisting a subordinate squad leader, often used for collaboration between platoons in a company.

A company-sized unit is usually commanded by a captain, assisted by a sergeant major. The command staff usually consists of a company commander, a sergeant major, in addition to a company chief of staff and company headquarters. Two or more platoon leaders, platoon sergeants, and four or more squad leaders are subordinate.