The Pathways study aimed to inform the ongoing debate in the juvenile justice system regarding the treatment and processing of serious adolescent offenders as they transition from adolescence into early adulthood. Between 2000 and 2003, over 1,300 adjudicated youths from Arizona and Pennsylvania's juvenile and adult court systems completed baseline assessments. Participants were at least 14 and under 18 years old at the time of their committing offence and were found guilty of a serious offence. An adult informant (usually a parent) was also interviewed at baseline. Follow-up interviews occurred at 6, 12, 18, 24, 30, 36, 48, 60, 72 and 84 months past baseline. Information was also gathered from court records.