The prevalence and correlates of benzodiazepine use and anxiolytic abuse and dependence are examined in a sample of 427 patients in Toronto, Canada, who met lifetime DSM-III criteria for alcohol abuse or dependence. The patients were evaluated with the NIMH-DIS and other standard psychiatric and substance abuse rating scales. Forty per cent were recent users of benzodiazepines and 20% had abused or been dependent upon anxiolytics, including benzodiazepines, during their lifetime. Patients with antisocial personality disorder (ASPD) were at higher risk for an anxiolytic disorder as were women and the unemployed. Recent users of benzodiazepines showed more current psychological distress, depressive symptomatology and more severe substance abuse problems than other patients and were more likely to have a lifetime DSM-III anxiety disorder. Patients with anxiolytic disorders, even if ASPD was controlled for, showed more psychiatric impairment and drug abuse problems than the remaining patients. Of those with a positive urine screen, 46% did not report using benzodiazepines in the previous week. Nineteen per cent of the patients who did not report benzodiazepine use in the previous week had a positive urine screen and were more likely to be found in the detoxification unit.