As family systems research has expanded, so have investigations into how marital partners coparent together. Although coparenting research has increasingly found support for the influential role of coparenting on both marital relationships and parenting practices, coparenting has traditionally been investigated as part of an indirect system which begins with marital health, is mediated by coparenting processes, and then culminates in each partner's parenting. The field has not tested how this traditional model compares with the equally plausible alternative model, in which coparenting simultaneously predicts both marital relationships and parenting practices. Furthermore, statistical and practical limitations have typically resulted in only one parent being analyzed in these models. This study used model-fitting analyses to include both wives and husbands in a test of these two alternative models of the role of coparenting in the family system. Our data suggested that both the traditional indirect model (marital health to coparenting to parenting practices), and the alternative predictor model where coparenting alliance directly and simultaneously predicts marital health and parenting practices, fit for both spouses. This suggests that dynamic and multiple roles may be played by coparenting in the overall family system, and raises important practical implications for family clinicians.