Affect or mood appears to exert potent effects on the motivation to use nicotine.3-5 For instance, among smokers, symptoms of nicotine dependence are correlated with the magnitude of affective symptoms of depression.6 In population-based studies, smokers are more likely than nonsmokers to have symptoms of affective disorders.6 Persons with a negative affect are more likely to start smoking and less likely to be able to quit7-9 — effects that may be related to changes in dopaminergic activity in the brain.10 Antidepressants or anxiolytics may therefore be efficacious cessation aids.3,11 Hurt and colleagues12 demonstrated that bupropion is an effective smoking-cessation aid: at 12 months, the abstinence rates were 23 percent among subjects assigned to receive 300 mg of bupropion per day for 7 weeks and 12 percent among subjects assigned to receive placebo. We compared bupropion, placebo, a nicotine patch,2 and a combination of bupropion and the nicotine patch with regard to efficacy.13 We also examined whether treatment with bupropion ameliorates nicotine-withdrawal symptoms such as negative mood.