Examined the effect of peer problem behavior, the absence of a father or equivalent in the home, and the mother-adolescent relationship as predictors of adolescent problem behavior in a sample of 112 African American adolescents. Statistical analyses compared a moderator model to a mediational model and a cumulative risk model. As predicted, the moderator model was superior to the alternative models. Specifically, whereas the mediational model predicted that the effect of father absence and the mother-child relationship upon adolescent problem behavior would be mediated by peer problem behavior, neither effected peer problem behavior or adolescent problem behavior. Similarly, a cumulative risk index did not predict either child or parent reports of problem behavior, and was not sensitive to specific contingencies which existed between the predictor variables. In contrast, an interactive, moderator model described the data quite well. This model suggested that father or equivalent absence magnifies the negative impact of peer problem behavior, while a positive mother-adolescent relationship attenuates this risk. A strong mother-adolescent relationship also served to protect adolescents in father absent homes from the risk of peer problem behavior.