This study reports on the development and validation of the Fatherhood Research and Practice Network coparenting perceptions scale for nonresident fathers. Although other measures of coparenting have been developed, this is the first measure developed specifically for low-income, nonresident fathers. Focus groups were conducted to determine various aspects of coparenting. Based on this, a scale was created and administered to 542 nonresident fathers. Participants also responded to items used to examine convergent and predictive validity (i.e., parental responsibility, contact with the mother, father self-efficacy and satisfaction, child behavior problems, and contact and engagement with the child). Factor analyses and reliability tests revealed three distinct and reliable perceived coparenting factors: undermining, alliance, and gatekeeping. Validity tests suggest substantial overlap between the undermining and alliance factors, though undermining was uniquely related to child behavior problems. The alliance and gatekeeping factors showed strong convergent validity and evidence for predictive validity. Taken together, results suggest this relatively short measure (11 items) taps into three coparenting dimensions significantly predictive of aspects of individual and family life.