We propose to extend the Northwestern Juvenile Project to examine the developmental patterns of drug use and disorder and risk for HIV/AIDS and other sexually transmitted infections (STIs) as juvenile justice youth age from adolescence to emerging adulthood and young adulthood. This study responds to NIDA's new initiatives in health disparities in HIV/AIDS in minority populations, specifically the nexus of drug abuse, criminal justice involvement, and HIV/AIDS among African Americans. African Americans comprise 12% of the US population but 40% of incarcerated populations and 50% of new cases of HIV/AIDS. At year-end 2004, nearly 100,000 juveniles and nearly 2.1 million adults were incarcerated. We will continue to study a racially/ethnically diverse sample (n=758;330 females, 428 males;412 African Americans, 137 non-Hispanic whites, 207 Hispanics, 2 other race/ethnicity) of persons who were arrested and detained in Cook County (Chicago) Illinois, aged 10-18 years at recruitment (1997-1998). Since recruitment, data have been collected on the development of substance use and disorders, risk and protective factors, and HIV/AIDS risk behaviors. Participants are re-interviewed whether they are (re)incarcerated or back in the community. We propose to conduct annual interviews 10, 11, 12, and 13 years post-baseline, collect records, and test for HIV infection and selected STIs. Focusing on racial/ethnic disparities, gender and age differences, and effects of incarceration, we will: (1) describe patterns of drug use and disorder - onset, persistence, desistence, and recurrence -- as juvenile justice youth age from adolescence to emerging adulthood and young adulthood;(2) describe patterns of HIV/AIDS risk behaviors during this same period;(3) describe the prevalence and incidence of HIV infection and other STIs;and (4) examine the relationship between drug use and disorder and HIV/AIDS risk behaviors. Extending the Northwestern Juvenile Project allows us to leverage the data already collected to examine health disparities and the role of disproportionate minority confinement in the development of drug use and disorder and HIV/AIDS risk;to identify risk and protective factors that are potentially malleable;to identify points of intervention at key developmental periods;and to extend theoretical models - developed in general population adolescents - to correctional populations.