OBJECTIVE: Persons with psychiatric illnesses are about twice as likely as the general population to smoke tobacco. They also tend to smoke more heavily than other smokers. This critical review of the literature identified 24 empirical studies of outcomes of smoking cessation approaches used with samples of persons with mental disorders. METHODS: The authors conducted searches of large health care and other databases for the years 1991 through 2001, using the key terms smoking, smoking cessation, nicotine, health/hospital/smoke-free policy, and psychiatry/ mental/substance abuse disorders. RESULTS AND CONCLUSIONS: The majority of interventions combined medication and psychoeducation. Although the studies were not uniform enough to allow a meta-analysis, the recorded quit rates of patients with psychiatric disorders were similar to those of the general population. Clinicians could usefully devote more effort to smoking cessation in populations with mental illness or addictions.