This ethnographic study of the Japanese American community in San Francisco is stated to be aimed at showing how the cross cultural study of personality changes throughout the life style can enrich the understanding of man. Chapters describe collective life in Japan Town against the background of its history; inspect respondents' perceptions of their own past in detail, and the way in which these perceptions affect relations between the generations; introduce the theoretical discussion of the effects of acculturation on the community, family, and individual, and briefly review traditional uses of the concept of acculturation; discuss concrete changes in values and behavior that characterize the Japanese Americans; turn to the effects of acculturation on the individual; introduce the concept of adult personality development into the study of acculturation; describe the typical life cycle in traditional Japanese culture and show how Americanization has changed this pattern; review the main developmental problems of each generation; summarize the author's view of the uses of social science; and, discuss some theoretical implications of the techniques used in the study. (Author/JM)