Three models (independent, interdependent, and mediational) were hypothesized in this study, to examine the interrelation of personality, family, and peer determinants and their effects on tobacco use by young adults. Mothers were first interviewed about their children when they were between the ages of 1 and 10 years old. Three subsequent interviews were conducted with the children when they reached adolescence and young adulthood. Results show support for the mediational model. In accordance with family interactional framework conceptions, there was a sequence in patterning: from parenting during early adolescence; to personality and peer factors, extending to smoking in late adolescence; and culminating in smoking in adulthood. With a developmental approach, a number of psychosocial measures were related in both younger and older children. Nevertheless, some interesting developmental differences emerged. The findings suggest at least four possible targets for therapeutic or preventive intervention: the parent, the child, the adolescent, and the peer group.