The study found that Hispanic clients were more often treated for heroin use than White clients, and they were more often referred to treatment by the criminal justice system. White clients were more likely to receive individual counseling than Hispanic clients. Hispanic clients had fewer mental disorders co-occurring with substance abuse compared with White clients, particularly diagnoses of depression or anxiety disorders; however, accurate mental health diagnoses may be difficult to make within the Hispanic population, due to a variety of client and provider factors. As Hispanics increase in the population (they showed the highest percentage increase of any race/ethnic group identified by the 2006 U.S. Census), some of the issues addressed in substance abuse treatment will change, particularly in geographic areas where Hispanics are in the majority. Culturally relevant models of treatment must be developed, and treatment may occur more often in Spanish. Other factors that may receive priority are client educational levels and rates of criminal justice referrals. Study data were obtained from the Alcohol and Drug Services Study (ADSS), which was a nationally representative study that described the characteristics of facilities, clients in treatment, and treatment outcome in the specialty substance abuse treatment system. The specialty substance abuse treatment system involves providers who focus exclusively on the treatment of substance use disorders. A client was coded as Hispanic if his/her ethnicity was identified as such in the client interview or the treatment record. 4 tables and 39 references