The stage of change approach to smoking cessation posits that smokers can be divided into categories based on the extent to which they are motivated to quit smoking. Recent research, however, suggests that the stage of change algorithm systematically misclassifies smokers by underestimating motivation to quit. The authors tested the hypothesis of the current study by contrasting the stages of change with the contemplation ladder (an alternative measure of motivation to quit smoking) using cross-sectional data on 10 cessation-relevant variables. The sample consisted of 401 adolescent smokers. The results were consistent with the hypothesis. The cross-sectional analyses indicated that the contemplation ladder is a more discriminating measure of motivation to quit, and that the stage of change algorithm is an unnecessarily imprecise instrument. (Published Abstract)