This is an abridged version of the Carnegie Council's study of adolescent development. The recommendations are based on six concepts about adolescence, particularly early adolescence. One concept is that the years from age 10 through 14 are a crucial turning point in life development; this period, therefore, is an optimal time for interventions to foster effective education, the prevention of destructive behavior, and the promotion of enduring health practices. Another basic concept of the report is that education and health are related; destructive or health-damaging behaviors in adolescence tend to occur together, as do positive, health-promoting behaviors. Further, many problem behaviors in adolescence have common antecedents in childhood experience; one is academic difficulty; another is the absence of strong and sustained guidance from caring adults. Another basic perspective of the report is that preventive interventions are more likely to be successful if they address underlying factors that contribute to problem behaviors. A final tenet of the report is that the essential requirements for ensuring healthy development must be met through the joint efforts of pivotal institutions that shape adolescents' experiences. These pivotal institutions must begin with the family and include schools, health care institutions, a wide array of neighborhood and community organizations, and the mass media. This report provides detailed analyses and proposals that pertain to these basic concepts. Chapter references, a list of 29 programs designed for positive youth development, and a 67- item bibliography