This is a print on demand edition of a hard to find publication. A significant number of youth in detention suffer from psychiatric disorders. Research indicates that providing detained youth with mental health services may reduce recidivism. This report measured the prevalence of alcohol, drug, and mental disorders among youth detained at the Cook County Juvenile Temporary Detention Center in Illinois. The study examined the prevalence of psychiatric disorders among youth by gender, race and ethnicity, and age. Nearly two-thirds of males and three-quarters of females met diagnostic criteria for one or more psychiatric disorders. This report presents info. that can help the juvenile justice system detect youth with psychiatric disorders and respond with an integrated system of services. Illustrations.