Dr. Clark, social psychologist, college professor, a Negro who lived in Harlem for forty years and who has recently been associated with its problems from the top level of Haryou, takes the role of ""involved observer"" to approach the combined problems of the confined Negro and the slum. The ghetto he analyzes here is the three-and-one-half square miles containing 232, 792 people that make up Harlem (excluding Spanish Harlem). He examines its social dynamics (unemployment and menial jobs result in family instability); psychology (the Negro male has a difficult time asserting his manhood in face of the dominant white); pathology--chronic, self-perpetuating (as the influence of gangs has declined, that of drug addiction has increased); schools--separate but unequal (the ""cultural deprivation approach"" is seductive: if students were expected to learn and so taught they would progress); the power structure (the effective exercise of power is severely crippled by the inexperience of its own political leaders). The strategy for change must be based on the understanding that the Negro's problems are essentially American and on the empathy of outsiders. Dr. Clark tempers his aims with the re-assurance that ""in contemporary society, no one Negro or white can be totally free of prejudice""; yet each race needs the other. Most interesting here: the insight into the psycho-social dilemmas of the Negro, the Negro response to the wide spectrum of leadership embodied in Adam Clayton Powell and Dr. Martin Luther King, Jr. Relevant, informative.