Significant concerns exist about youth who initiate sexual behavior at young ages: their numbers are increasing in the U.S., they disproportionately include children of color from families living in poverty, and they are not served by current prevention programs that target teenagers (Albert et al. 2003). Their risks for STDs and HIV/AIDS are dramatically higher than their more advantaged peers who initiate sexual activity at later ages, and yet very little is known about nature of their early risks or the concurrent preadolescent risk behaviors that may complicate prevention program design and moderate intervention effectiveness. The present study offered a unique opportunity to inform future prevention program design by examining the early childhood antecedents and preadolescent correlates of early sexual debut in a large, diverse, multi-site sample of vulnerable children at-risk due to elevated rates of childhood conduct problems and family adversity. The large sample size and study design made it possible to go beyond the variable-centered linear predictions provided by prior longitudinal studies, and to explore variations in individual risk profiles using person-oriented analyses. In addition, the present study
