Cigarette smoking has clearly been related to a number of major health disorders. Most smokers who quit smoking do so without the aid of formal cessation programs. Little empirical data are available on interventions to facilitate self-quitting, or on factors that predict relapse or successful abstinence for unaided quitters. The proposed project is designed to evaluate the long-term effects of various self-help interventions, and determinants of relapse/maintained abstinence for a large population of self-quitters. Specifically, a three-study series is planned. Study 1 will evaluate the relative effectiveness of three relapse prevention interventions offered by a community-based hotline service targetting self-quitters. The most effective intervention package will be used in Study 2, in which 10 counties will be randomly assigned to a self-help manual or self-help manual and access to the hotline condition. Subjects will be followed for up to 4 years. Study 3 will assess factors related to relapse or maintained abstinence for hotline callers in Studies 1 and 2. Callers will be interviewed at or near the time of a relapse episode, and recontacted at various follow-up intervals.