This study examined prospective pathways from exposure to interparental violence (EIPV) during infancy (ages 0–24 months) and toddlerhood/preschool (ages 25–64 months) to intimate partner violence (IPV) perpetration and victimization in adulthood (ages 23, 26, and 32 years) using 2 complementary approaches. Building on past findings, a variable-oriented approach was used to examine the effects of developmental timing of EIPV in infancy versus toddlerhood/preschool to IPV involvement in early adulthood, at age 23 years. A person-oriented approach next examined whether continuity and change in IPV (persisting, increasing, and decreasing vs. nonviolent patterns) across the transition from early adulthood to adulthood (ages 26 to 32 years) were predicted by developmental timing of EIPV within early childhood and/or contemporaneous adulthood factors (life stress and behavior problems). In this fully prospective longitudinal study beginning at birth, mothers reported on EIPV in infancy and toddlerhood/preschool, and participants (N = 179) reported on IPV and contemporaneous stress and behavior in early adulthood and adulthood. Results indicated that according to the variable-oriented approach, EIPV in toddlerhood/preschool but not in infancy predicted both IPV perpetration and victimization at age 23. The person-oriented approach revealed that, along with life stress and externalizing behavior, EIPV in toddlerhood/preschool, but not in infancy, also differentiated patterns of IPV from ages 26 to 32. Findings converge on toddlerhood/preschool as a particular promising developmental period to intervene and deter long-term effects of EIPV on IPV across the transition from early adulthood to adulthood.