The Residential Student Assistance Program in Westchester County, NY, was based on employee and student assistance programs, but designed for adolescents housed in various types of institutions and facilities. Professional student assistance counselors (SACs) were assigned to county correctional facilities, residential treatment centers, foster care facilities, and non-secure residential facilities for juvenile offenders sentenced by the court. SACs provided culturally sensitive substance use prevention and intervention services to African American or Hispanic teenagers who had committed violent or delinquent acts; had been physically, sexually, or psychologically abused; had experienced chronic failure in school; or had experienced mental health problems, including some who had attempted suicide. Evaluations showed a marked decrease in alcohol, marijuana, and tobacco use after the intervention. Seventy-two percent of alcohol users stopped drinking alcohol; 58.8 percent of the marijuana users ceased smoking marijuana; and 26.9 percent of the smokers quit using tobacco.