Adolescents embody the best hopes of American society. Their vital role in shaping our future lends particular significance to their success in negotiating the passage from childhood to adulthood, while their intensity and visibility often make them barometers of social change. It is all the more remarkable, then, that this critical period has only recently captured the full attention of researchers. At the Threshold presents the long-awaited findings of the Carnegie Foundation study on adolescence. It offers a comprehensive overview of what investigators are learning about normal development and provides an interdisciplinary synthesis of research into the biological, social, and psychological changes occurring during this key stage in the life span. While focusing on the contexts of adolescent life-social and ethnic, family and school, leisure and work-it also addresses how researchers are doing in the effort to understand the intersection of processes that initiate and sustain adolescent development and to characterize the extraordinary changes that occur during these years. Contrary to popular belief, large numbers of young people continue to mature into productive members of society. At the Threshold seeks to allow professionals and nonprofessionals alike important access to the reality of normal adolescent experience. The authors recognize that only if we begin to understand and clearly articulate the parameters of successful adolescent development can we hope to intervene with those individuals whose lives seem aimed toward unsatisfactory futures.