Objective: The objective was to disentangle the relationship between offending, ADHD, and comorbid risk factors. Method: A total of 11,388 students in further education completed a questionnaire, which measured nonviolent and violent delinquency, current ADHD symptoms, conduct disorder, substance use, association with delinquent peers, emotional lability, anger problems, violent attitudes, and low self-esteem. Results: The nonviolent and violent delinquency measures correlated significantly with all the predictor measures, with small to large effect sizes. Multiple regressions showed that after controlling for age and gender, ADHD contributed 8.2% and 8.8% to the variance in nonviolent and violent delinquency, respectively, but these effects were largely mediated by the comorbid measures, particularly substance use, association with delinquent peers, and conduct disorder. Conclusion: The relationship between ADHD symptoms and offending among young people is largely explained indirectly by comorbid factors. A key prevention is to address substance use problems and association with delinquent peers. (J. of Att. Dis. XXXX; XX(X) X-XX)