This study examined relationships between smoking and antismoking practices of parents and early onset of smoking among elementary-grade children. The parent practices we investigated were direct modeling of cigarette smoking and antismoking socialization variables, such as setting rules to eliminate cigarette smoking in the home, awareness of children's smoking behaviors, and making clear the disciplinary consequences of cigarette smoking. Surveying a sample of 1.213 third- and fifth-grade children, we found (1) children's risk of early onset of smoking increases with level of exposure to parent smoking models; (2) if one or both parents are current smokers, children who have never tried smoking have significantly greater risk of intending to smoke, perceiving easy access to cigarettes, and being ambivalent about smoking; (3) risk rates for children of former smokers indicate that parents' quitting smoking does not eradicate the effects of parent modeling; and (4) children whose parents engage in antismoking socialization have significantly lower rates of smoking onset, even if parents are current smokers. The implications of these results for preventive intervention and future research are discussed.