This report is based on the Symposium on Counterinsurgency held at RAND’s Washington Office during the week of 16 April 1962. The purpose of the symposium was to bring together those with first-hand experience of guerrilla and counterguerrilla warfare for informal exchanges of information that might lead to fresh insights and a detailed body of expert knowledge. The subjects discussed include patterns and techniques of counterinsurgency, effective organizational and operational approaches, political action, psychological warfare, intelligence and counterintelligence, and requirements for victory. This new release of the report includes a new foreword by Stephen T. Hosmer that elucidates the relevance of this symposium to contemporary guerrilla and counterguerrilla operations.