Promotion and prevention focus have been shown to uniquely predict the initiation and maintenance of behavior change, but the behavioral tasks underlying these effects have not been specified. We examined the effects of regulatory focus on how smokers responded to initial slips and whether smokers were able to avoid slips after initial cessation. After slipping, smokers higher versus lower in promotion focus were more likely to quit again, particularly if they were high in self-efficacy. Of participants quit for 2 months, smokers higher versus lower in prevention focus more consistently avoided slips, but only if they were high in self-efficacy. Implications for regulatory focus theory and behavior change theory are discussed.