The current study tested a prospective (over 9 years) moderated-mediational model in which adolescent psychopathology symptoms (i.e., internalising, externalising, and combined) mediated the association between exposure to intimate partner violence (IPV) in middle childhood and their perpetration of IPV as a young adult. There was a small, significant direct effect from exposure to IPV to young adult perpetration, which was only mediated through adolescent externalising behaviour. Furthermore there were differences in youth's sensitivity to exposure to IPV across developmental periods. For males, the effects of IPV exposure were intensified during the transition to adolescence. In contrast, for females, the effects were increased during the transition to adulthood.