For the 192 cases that provided relevant reliable information, 68 percent of the cases involved a father with a substance-use disorder; for the 295 cases with relevant reliable information, 45 percent involved a mother with a substance-use disorder. For the 159 cases with relevant reliable information, 27.7 percent involved both parents with a substance-use disorder. The study found that youth whose fathers had a substance-use disorder were more likely to engage in offending behavior at an earlier age than were youth whose fathers did not have a substance-use disorder. In addition, youths whose fathers had a substance-use disorder were more likely to have a higher number of adjudicated offenses and a longer period of probation compared with their counterparts whose fathers did not have a substance-use disorder. Regarding age of onset for delinquency, no significant differences were found between youths whose mothers had a substance-use problem compared with youths whose mothers did not have a substance-use problem; however, youths with maternal substance abuse had more adjudicated offenses. Youths with two substance-abusing parents were most at risk for a higher number of adjudicated offenses and longer probation supervision. The findings clearly show that intervention for court-involved youth should take into account not only any substance abuse by a parent or parents, but also the gender of the substance-abusing parent. Further research should determine whether the delinquency outcomes found in this study hold true for both substance abuse and substance dependence. This retrospective study tracked adjudicated youths and their families over a 4-year period. Court and probation records provided data on delinquency and juvenile court outcomes. 2 tables, 3 figures, and 54 references