This study examined relations between aspects of family functioning and positive and negative dimensions of forgiveness. Increased understanding of one's partner and decreased anger about betrayal characterize positive forgiveness, whereas experiences such as holding a grudge and desiring revenge indicate negative forgiveness. The sample included 87 wives and 74 husbands who reported experiencing a significant betrayal, their partners, and their adolescent children. Analyses of reported forgiveness revealed that more negative forgiveness was associated with lower marital satisfaction for husbands and wives; trust partially mediated this relationship for husbands and wives. Greater positive forgiveness reported by husbands and wives predicted their own reports of a stronger parenting alliance, whereas greater negative forgiveness reported by husbands and wives predicted their spouses' reports of a weaker parenting alliance. For wives, more negative forgiveness also predicted higher levels of children's perceived parental conflict, and parents' reported conflict mediated this association for wives. Findings suggest that forgiveness of a marital betrayal is significantly associated with marital satisfaction, the parenting alliance, and children's perceptions of parental marital functioning. (PsycINFO Database Record (c) 2010 APA, all rights reserved). DOI: 10.1037/a0014354