Abstract: This study presents findings of a mother-only coparenting intervention conducted in conjunction with fathers' participation in a fatherhood program. Specifically, this study sets out to determine whether there is an association between mothers' participation (N=127) in the group-based intervention, Understanding Dads TM, and changes in mothers' reports of the coparentng relationship and mothers' coparenting attitudes. The findings of this one group pretest/posttest/follow-up study showed that mothers reported fewer disagreements and less undermining of fathers following participation in the intervention. Mothers also indicated greater confidence in their ability to coparent cooperatively with the father after participation. Implications for fatherhood programs are discussed.