The findings support the feasibility and acceptability of using CM for adolescent smokers with a moderate to heavy smoking habit. Attendance rates were excellent for measuring breath levels of carbon monoxide (indication of smoking). Participants were positive about their involvement in the study, and most indicated they could have continued in the program for several more weeks. Trends in the data suggest that CM reduces adolescent smoking, with effect sizes due to CM being mainly in the medium range in terms of abstinence and carbon monoxide levels. Results suggest that the inclusion of wider data-collection time windows and more data collection points (i.e., continuing CM through weekends) may better capture adolescent smoking rates. Providing breath samples immediately before and after school may result in fewer opportunities to engage in smoking, since most high schools prohibit smoking during school hours. Nineteen adolescents completed three 7-day phases: reinforcement for attendance and provisions of breath samples (RA) phase; a washout phase; and a CM phase, with order of CM and RA counterbalanced. In addition, participants were randomized to one of two reinforcement conditions during the CM phase: a CM-Abstinence condition (n=9), wherein participants earned reinforcement only for carbon monoxide levels indicating abstinence; and a CM-Reduction condition (n=10), wherein participants earned reinforcement for reductions from baseline carbon monoxide levels for the first half of the CM phase, followed by an abstinence contingency for the remainder of the phase. 1 table, 2 figures, and 41 references