This study examined the independence and interplay between cognitive risk factors (poor executive function/emotion understanding) and maternal risk factors (low education/high depression) for preschool problem behaviors, indexed by multi-measure, multi-informant (mother/teacher/ researcher) ratings. A socio-economically diverse sample of 235 children (131 boys, 104 girls; mean age = 4.25 years) completed five executive-function tasks and four emotion-understanding tasks. Controlling for effects of gender, verbal ability and maternal education, individual differences in child problem behavior scores showed significant independent associations with executive dysfunction, emotion understanding and maternal depression. For girls, low maternal education amplified the relationship between executive dysfunction and problem behaviors. In addition, executive dysfunction mediated the relationship between maternal depression and problem behaviors; both executive dysfunction and poor emotion understanding mediated the relationship between low maternal education and problem behaviors. These results demonstrate the cumulative and complex nature of risk for preschool problem behaviors. (Contains 3 tables and 3 figures.)