According to police statistics, the crime rates in Japan have been declining progressively since 1953 except for a slight rise in 1975 and 1976 and then again in 1978. These drops are attributed to a social structure that discourages crime but also masks the actual levels of crimes committed. A principal social factor is the centrality of the group in Japanese social structure: the value of the individual is a function of his or her usefulness to the group. The principal elements of the group's structure are the family, the professional organization, and the neighborhood. Violations of the law in favor of the group norms may also classify the individual as an outsider. The hierarchy within the group is established by age and seniority. While the head of the group makes decisions, all decisions require consensus. Group relations are vertical, formal, and dominated by a certain etiquette. Aggressiveness and the idea of vengeance are not accepted in the life of the society. Within this social structure, police efforts are highly successful.The crime clearance rate is about 86 percent. Police success is attributed to good training and social prestige. Officers keep careful track of activities in their local districts, even interviewing resident families twice a year to ascertain potential problems. The effectiveness of the police is heightened by their omnipresence and their amiable helpfulness. Notes and a bibliography are supplied.