In addition to the interview, most of the juveniles (approximately two-thirds) also provided a urine sample that was analyzed for six classes of drugs. The DUMA juvenile data were examined for the years 1999 to 2002. The urine screen tests confirmed that many of the juveniles had used illicit substances in the period before their arrest. Forty-eight percent of the detainees tested positive for cannabis; 12 percent tested positive for opiates; and 11 percent tested positive for amphetamines. Overall, 55 percent of juvenile arrestees tested positive for one of the six drugs. The urinalysis results confirmed self-report data that young female detainees were more likely to test positive for drugs such as cocaine, amphetamines, or opiates than male detainees. They were also more likely to use multiple drugs or drugs other than cannabis. Property offenses were the most common offenses with which juveniles were charged. Juveniles who had recently used heroin, cocaine, or amphetamines self-reported much higher levels of offending in the past 12 months. Few juveniles reported accessing treatment, and when they did, the treatment was often court-mandated. The age of drug initiation was lower than previously believed, thus highlighting the need for continued commitment to early intervention and education. 3 tables and 21 references