During the past 10 years a good deal of effort has focused on preventing cigarette smoking among adolescents. This effort has often been made without a clear understanding of (1) which groups within the population are at highest risk, (2) which variables are associated with habitual smoking rather than experimentation, and (3) how the influence of those factors differs across levels of the variables that locate the adolescent in his or her social environment. The purpose of this research was to use a social learning model to address those three questions. The data were collected as part of the first wave of a longitudinal research project on adolescent smoking behavior. The results indicated that the ability to integrate smoking into the adolescent's lifestyle, followed by positive attitudes toward smoking and association with peers who smoked, had the greatest influence on the likelihood of habitual smoking. In addition, adolescents who were at the extreme ends of the popularity continuum or were the least integrated into the school environment were at the greatest risk for becoming habitual smokers.