Results support a three-solution model for juvenile females and a six-solution model for juvenile males. Prior maltreatment as children (substantiated as well as alleged but dismissed) predicted moderate to higher level offending for both males and females, with the exception of one higher level but decreasing trajectory for males. Living in a blended family (mother and stepfather or father and stepmother), living with grandparents, and living with relatives at first offense all correlated with a moderate level of offending trajectory for males. Living in foster care at first offense was a predictor for both lower level and higher level offending by females. Both the three-solution female model and the six-solution male model predicted incarceration. The report advises that attending to the victimization, trauma, and psychosocial situations that negatively impact female and male youth offenders is an advocacy issue that those in social work, criminal justice, and psychology must support through research and evidence-based program development and evaluation. This requires the development and maintenance of cross-systems partnerships among child welfare, juvenile justice, mental health, school systems, and scholarly researchers. Semiparametric group modeling was used to specify offending trajectories for a response variable operationalized as a frequency count of unique complaints by age. Time-stable psychosocial and systems-level covariates were also examined as predictors of likely trajectory group membership. The probability of trajectory group membership was investigated as a predictor for secure incarceration. 16 tables, 5 figures, 44 references, and appended supplementary information