Using prospective, longitudinal data from the Pittsburgh Youth Study (PYS), Boots gauges the temporal impact of childhood and adolescent mental health problems on the development of serious offending behaviors in boys. She converts data from both parent and teacher reports of psychopathological problems to create DSM-oriented scales for Oppositional Defiant, Attention-Deficit/Hyperactivity, Anxiety, and Affective Problems. When compared to DSM diagnoses, these scales offer an innovative and more continuous form of measurement with distinctions between normal, borderline, and clinical levels of these mental health problems. Regression analyses across 24 models indicate that three different teacher-reported DSM-oriented mental health problems emerged at three different stages of development as significant predictors of serious violence over the lifecourse.