This paper examines the developmental antecedents of interpartner violence (IPV) victimization and perpetration in a New Zealand birth cohort (n = 828). The study found: (a) IPV occurred in 70% of relationships, with conflict ranging from minor psychological abuse to severe assault; (b) men and women reported similar experiences of victimization and perpetration of IPV; (c) exposure to abuse in childhood, family dysfunction and adversity, childhood and adolescent conduct problems, and alcohol abuse/dependence were significant predictors of IPV victimization and perpetration at age 25; and (d) the antecedents of IPV were largely the same for males and females, although the specific effects of these risk factors differed according to gender. Conduct disorder was more strongly predictive of IPV for females, whereas family adversity was more strongly predictive of IPV victimisation for males.