Dr. Lacoursiere is a psychiatrist on the faculty of the Menninger School and an experienced group therapist. Still, this book must be categorized as sociology rather than psychoanalysis or even psychology. He has identified a series of developmental stages through which, he says, all groups evolve. He describes and elucidates these stages in many kinds of group—not only therapy groups but academic classes, business management teams, neighborhood action committees, and others—chiefly by reporting in detail on many studies done by psychologists, psychotherapists, sociologists, and educators (references cover nearly 19 pages).