Intended primarily for researchers and prevention program personnel, this booklet provides current background information on the continuing problem of smoking among children and adolescents. In the first brief section, research findings concerning American youth's current smoking patterns and beliefs are described. The second section considers four conceptual models in developmental and social psychology which appear potentially useful in generating hypotheses to account for the initiation of smoking among the young and in providing conceptual bases for prevention programs. The third section reports findings of studies focusing on several psychosocial factors influencing the decision to smoke: changing sex roles, parental smoking habits, parental acceptance of children's smoking, siblings who smoke, rebellion against family authority, peer pressures, the school environment, mass media influence, individual characteristics, and perceptions of the dangers of smoking. The fourth section reports critical evaluations of some current prevention programs, such as public information campaigns and school programs. In conclusion, recommendations for future research and prevention programs are offered. (RH)