Objective: Health care facilities are increasingly implementing policies that ban smoking. A concern has been raised that these policies may have a negative impact on smokers who are mentally ill or substance dependent. The authors conducted a literature review to analyze the relevant empirical evidence. Methods: Major health care databases were searched. Major search terms included smoking, smoking cessation, nicotine, health policy, hospital policy, smoke-free policy, psychiatric disorders, and substance use disorders. The search was limited to empirical studies, which were analyzed on the basis of design, the behavioral indicators monitored, and the results of questionnaires. Results and conclusions: A total of 22 investigations of the impact of total or partial smoking bans suggest that the policies have had no major long-standing untoward effect in terms of behavioral indicators of unrest or compliance. However, the policies appear to have had little or no effect on smoking cessation. Smoking cessation strategies should be an inherent component of policies that ban smoking.