Intervention Project. Results identified two classes of youths: Class 1(n=9) - youths with low levels of delinquency, mental health and substance abuse issues; and Class 2(n=37) - youths with high levels of these problems. Comparison of these two classes on their urine analysis test results and parent/guardian reports of traumatic events found significant (p less than 0.05) differences between them that were consistent with their problem group classification. Our results have important implications for research and practice. (Contains 1 note and 5 tables.)