To test the hypothesis that early attentional persistence will moderate the effect of infant negative emotionality on social competence, problem behavior, and school readiness at age 3, data collected as part of the NICHD Study of Early Child Care were subject to structural equation modeling analyses (N = 1,038). Consistent with Eisenberg et al.'s data on older children, high levels of negative emotionality were associated with low levels of social competence only when attentional persistence was poor. No such moderating effects of attentional persistence emerged in the case of behavior problems. And in the case of school readiness, findings indicated that high levels of negative emotionality predicted high levels of school readiness when attentional persistence was high, a result opposite to that found with respect to the prediction of social competence.