Increasing attention is being given to helping vulnerable youth transition successfully into adulthood and independence. Previous research has shown higher risks of criminal justice involvement, unemployment, teen pregnancy, behavioral health disorders, homelessness, and lower educational attainment for youth in child welfare systems. This study investigates the young adult outcomes of youth who age out of, or otherwise exit, Los Angeles County’s foster care system and/or juvenile probation system. Investigators analyzed a comprehensive data set of youth who exited foster care or probation in Los Angeles County in 2002 or 2004 linked to records of service utilization that stretched from 2005 to 2009 across seven Los Angeles County Departments and two California state agencies. This unique study looks at the relationship and dynamics between a number of domains including education, employment, health, mental health, criminal justice, and public welfare systems; and it is the first study to report on adult outcomes among the sub-group of “crossover” youth who are involved in both child welfare and juvenile justice systems.