Smoking cessation is increasingly considered to be a process rather then a discrete event. Several stage models that stress the process nature of behavior change have been developed in the last decade. In the present study, a stage model is investigated that categorizes smokers into four groups with increasing readiness to change: immotives, precontemplators, contemplators, and preparers. Smokers from the general population were recruited to participate in an investigation on smoking cessation interventions. At pretest, the anticipated positive and negative outcomes of quitting, perceived self-efficacy, and smoking behavior were assessed. Three and 14 months after the pretest, the follow-up measurements were conducted. The cross-sectional results showed that smokers in the four stages differed from each other on the factors pertaining to the positive outcomes and perceived self-efficacy. No differences between the four stages were detected concerning the number of cigarettes smoked a day, the nicotine dependence score, and the number of years smoked. The longitudinal results showed that the stage of readiness to change at pretest was highly predictive of quitting at both follow-ups. It is concluded that this stage model is worthy of support.