Results indicated that a strong predictor of delinquency in young adult men was a lack of orderly and structured family activities during adolescence. This finding held true after controlling for prior aggression and demographic factors. The findings did not, however, find evidence for a significant relationship between authoritarian and authoritative parenting styles and later male delinquency. Moreover, family factors that had previously been considered predictive of delinquency, such as socioeconomic status, parental supervision, punishment, and parental attachment were not significantly related to delinquent behavior during young adulthood. The findings thus suggest that traditional family factors impacting adolescence simply do not provide significant long-term predictions of delinquent activity during young adulthood for males. Data were drawn from 2 longitudinal studies: the Pittsburgh Youth Study (PYS) of 474 young males and the Child-Rearing and Family in the Netherlands Study (CFNS) of 128 families. The PYS was a prospective longitudinal study on the development of mental health problems, substance use, sexual behavior, and delinquency among boys in public schools in Pittsburgh’s inner city. The CFNS was a prospective longitudinal study of family functioning that started in 1990 with the goal of describing different forms of family relationships and child-rearing practices among Dutch families. Each dataset contained information for a period of at least 10 years. Data were analyzed using logistic regression models. Future studies should use a developmental perspective to investigate the relationship between delinquency and theoretically relevant family characteristics. Tables, footnotes, appendixes, references