This study examined whether particular forms of parental psychopathology are related to similar forms of comorbid psychopathology in offspring with attention deficit-hyperactivity disorder (ADHD). Parental disorders were assessed using maternal interviews, and child disorders were assessed using multiple-informant interviews for 111 clinic-referred boys (aged 7-12) with Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; American Psychiatric Association, 1987) ADHD. Associations between parental and child internalizing disorders and between parental and child externalizing disorders were found, but associations across categories of disorder (i.e., internalizing and externalizing) were not. Similar relationships were observed in 66 clinic-referred boys without ADHD. These findings support specific modes of familial transmission, in contrast to theories that comorbidity simply reflects more severe psychopathology in children with ADHD.