Despite previous research indicating that early negative child behavior and the quality of the parentchild relationship are predictive of later externalizing problems, few investigators have attempted to trace these antecedents back to infancy. In a sample of 100 infants from low-income families, it was possible to identify developmental sequences leading from infant persistence and lack of maternal responsiveness to later child disruptive, aggressive child behavior at ages 2 and 3. Gender differences were found with respect to the range and type of variables that showed continuity in predicting disruptive behavior. For boys, salient predictors of age 2 and age 3 externalizing behavior were maternal unresponsiveness, infant attention-seeking, aggression, and noncompliance, whereas for girls, infant noncompliance was related to both age 3 externalizing and internalizing problems. Antisocial behavior in childhood is important because of its direct cost to society in terms of damaged property and disruption of normal patterns of living, but it is also important because of the difficulty of treating delinquent youth and the possible emergence of later adult criminality (Loeber, 1982). Despite its costs and resistance to intervention, researchers have only recently begun to apply a developmental perspective to the study of externalizing behavior problems beginning early in childhood. Ultimately, this basic developmental information is necessary to the formation of risk groups, as well as for the determination of the optimal mode and timing of intervention. Although there are many contributing factors to the development of externalizing problems, such as low income, parental conflict, and parental criminality, two reviews (Loeber & Dishion, 1983; Loeber & Stouthamer-Loeber, 1986) have come to the conclusion that harsh, inconsistent discipline, inadequate supervision, parental rejection, and lack of involvement with the child are important factors across a broad range of studies. Thus family factors involving discipline practices and the quality of the parent-child relationship are at the forefront of results