Kathryn Edin and Joanna Reed review recent research on social and economic barriers to marriage among the poor and discuss the efficacy of efforts by federal and state policymakers to promote marriage among poor unmarried couples, especially those with children, in light of these findings. Social barriers include marital aspirations and expectations, norms about childbearing, financial standards for marriage, the quality of relationships, an aversion to divorce, and children by other partners. Edin and Reed note that disadvantaged men and women highly value marriage but believe they are currently unable to meet the high standards of relationship quality and financial stability they believe are necessary to sustain a marriage and avoid divorce. Despite their regard for marriage, however, poor Americans do not view it as a prerequisite for childbearing, and it is typical for either or both parents in an unmarried-couple family to have a child by another partner. Economic barriers include men's low earnings, women's earnings, and the marriage tax. In view of these findings, Edin and Reed argue that public campaigns to convince poor Americans of the value of marriage are preaching to the choir. Instead, campaigns should emphasize the benefits for children of living with both biological parents and stress the harmful effects for children of high-conflict parental relationships. Programs to improve relationship quality must address head-on the significant problems many couple face. Because disadvantaged men and women view some degree of financial stability as a prerequisite for marriage, policymakers must address the instability and low pay of the jobs they typically hold as well as devise ways to promote homeownership and other asset development to encourage marriage. Moreover, programs need to help couples meet the challenges of parenting families where children are some combination of his, hers, and theirs. Encouraging more low-income couples to marry without giving them tools to help their marriages thrive may simply increase the divorce rate. (Contains 89 endnotes.)