Visit 2 (Quit Day). Participants will complete self-report questionnaires on a laptop computer; and expired CO and weight will be measured in a private room to ensure confidentiality. Visit 2 takes approximately 40 minutes to complete. Participants randomized to the CM treatment will receive an additional payment if they self-report abstinence from smoking since 10 p.m. the prior evening, and their expired is CO level is < 10 ppm (please note that the less stringent cut-off of 10 ppm will be used to verify abstinence at the first visit only, due to the recency of quitting). Participants who do not attend will be contacted by phone to obtain their self-reported smoking status only.