The Minneapolis Department of Veterans Affairs Medical Center began an intervention for tobacco use in its inpatient substance dependency treatment program on June 19, 1988, including an institutional smoke-free policy and a smoking cessation program. Sequential substance-dependent patients admitted before institution of the policy (n = 455) were compared with patients admitted after institution of the policy (n = 457). Patients completed self-administered questionnaires regarding smoking practices and attitudes. Seventy-six percent of patients were current cigarette smokers. Fifty-eight percent of patients after institution of the policy described themselves as "not smoking regularly," compared with 19% of patients admitted before the institution of the policy. Similar proportions of patients admitted before and after the institution of the policy believed that quitting smoking would threaten recovery. Forty-one percent of patients hospitalized after institution of the policy abstained from smoking for more than 1 week during their hospital stay. Rates of early termination of treatment did not change. We conclude that concurrent intervention for nicotine addiction during inpatient treatment of substance dependence is associated with a temporary reduction in smoking and increased motivation to quit smoking.