Few studies have evaluated the separate contributions of maltreatment and ongoing quality of parent-child interaction to the etiology of antisocial personality features using a prospective longitudinal design. 120 low-income young adults (aged 18-23) were assessed for extent of ASPD features on the Structured Clinical Interview for Diagnosis-Axis II, for presence of maltreatment on the Conflict Tactics Scale, Traumatic Experiences Scale, and Adult Attachment Interview, and for referral in infancy to parent-infant clinical services. Fifty-six of these families had been studied longitudinally since the first year of life. In infancy, attachment disorganization and disrupted mother-infant interaction were assessed; in middle childhood, disorganized-controlling attachment behaviors were reliably rated. In kindergarten and second grade, behavior problems were assessed by teacher report. In cross-sectional analyses, maltreatment was significantly associated with ASPD features but did not account for the independent effect of early referral to parent-infant services on ASPD features. In longitudinal analyses, maternal withdrawal in infancy predicted the extent of ASPD features twenty years later, independently of childhood abuse. In middle childhood, disorganized attachment behavior and maladaptive behavior at school added to prediction of later ASPD features. Antisocial features in young adulthood have precursors in the minute-to-minute process of parent-child interaction beginning in infancy.