For greater commodity in consultation, conclusions or general axioms are printed in italics wherever they appear in the text. The book concludes with a lengthy bibliography. The author makes it very clear that his fundamental view of aggression is not Freud’s. He prefers an explanation in terms of S-R concepts and learning-theory. Using Frustration and Aggression, the pioneer monograph by Dollard and his associates, as a point of departure, he suggests modifications to their findings in the light of recent research. Berkowitz agrees with the Yale group that aggressive behavior is elicited by some form of frustration. But the various types of frustration and possible responses to it are myriad and their implications are of great concern to sociologists. Frustrations, and particularly economic frustrations, are the ideal breeding-ground for hostility against minority groups : there may be a displacement of hostility for the immediate frustrating agent or situation to a disliked group. The author discusses possible means for reducing hostility of this type, for no matter how great our present or future prosperity, frustrations are bound to occur in our society. The use of the mass media for the diffusion of messages advocating peace and harmony with minority groups is usually ineffective ; such messages are not heeded when they are dissonant with previous attitudes. Minimizing group differences, and, if possible, lessening minority &dquo; visibility &dquo; are much