Psychological factors are an integral part of all battlefields. Each unit movement and every conquest of terrain psychologically affect the battlefield participants and an audience of friendly, neutral, or hostile groups. The psychological effect of combat actions can be seen in the heightened morale of a successful unit or in the discouragement and fear of a defeated unit. Properly manipulated attitudes can modify the behavior and the combat effectiveness of the soldier and the unit. This manual provides information and guidance for the conduct of psychological operations (PSYOP) in general, limited, and cold war. The doctrine, techniques, and procedures found herein are applicable to conventional warfare, unconventional warfare (UW), and foreign internal defense (FID) operations. This manual should be used in conjunction with other official manuals and publications that provide staff organization procedures and guidance for doctrine, field operations, and maintenance of equipment.