The present study examined pathways leading to early externalizing problems from age 1 to 3½ in a design that took advantage of our knowledge of normative progression and normative socialization as well as findings from research on risk. A sample of 130 low-income participants was followed longitudinally from 12 to 42 months using observational measures of developmentally salient parenting and child disruptive behavior to predict early externalizing problems. Results are best accommodated by concepts such as transformation and transaction from developmental psychology. For boys, both child and parent variables predicted later externalizing. For girls and boys, the interaction between child noncompliance and maternal rejection was significant.