An estimated 40% of patients in mental health treatment settings engage in hazardous alcohol and/or drug use. One model of intervention that has been shown effective in medical settings to reduce alcohol use and/or promote engagement in addiction treatment is screening, brief intervention, and referral to treatment (SBIRT). Despite the effectiveness of SBIRT for risky alcohol use in medical settings, there has been no research on the effectiveness of SBIRT in mental health treatment settings. Given the proportionately large number of mental health patients who also engage in hazardous substance use, research is needed to find an appropriate and effective substance use intervention for patients in these settings.