Participants will be randomly assigned to one of four groups. Participants will receive either bupropion (150 mg for 3 days and 300 mg for 60 days) or placebo, starting one week prior to smoking quit day. They will then receive either active NRT (21 mg for 6 weeks, 14 mg for 1 week, and 7 mg for 1 week) or placebo, starting on quit day. Participants will be studied for up to 5 nights in a sleep lab. Sleep studies will include polysomnography measurements, including electrooculography of both eyes, activity of mentalis muscle and both anterior tibialis muscles, EEG, ECG, oxygen saturation, airflow, and respiratory efforts. Sleep studies will occur on the 2 nights prior to quit day, the quit night, and the 2 nights after quitting. Each sleep study will be followed by daytime measures. These will include a series of self-report instruments, sleepiness and performance measures, and physiological activity measures. Carbon monoxide levels will also be a daytime measurement and must fall below 10 ppm on the post quit days. All participants will receive bimonthly phone counseling for 12 months, starting on quit day. Participants will have follow-up evaluations at Months 3 and 12 in order to measure carbon monoxide levels and complete self-report instruments.