Spencer provides a history of the FMLN guerrilla special forces—known collectively by the acronym FES—in El Salvador. Trained in Cuba and Vietnam and utilizing techniques taken from the Viet Cong and the North Vietnamese army, the FES terrorized the armed forces of El Salvador from 1981 to 1992. After reviewing their training, Spencer examines the major operations of the special forces and gives an in-depth discussion of their tactics and methods. He concludes with a look at the special forces groups in other Latin American countries.

After reviewing their training, Spencer looks at the major operations of the special forces groups of three of the guerrilla factions—the FPL, ERP, and FAL—and provides an in-depth discussion of their major operation tactics and methods. He concludes with a look at the special forces groups in Argentina, Colombia, Cuba, Guatemala, Nicaragua, and Puerto Rico. This thorough examination of an often misunderstood approach to guerrilla warfare will be of great interest to researchers involved with contemporary low-intensity warfare and Latin American affairs.