Marriage and Child Wellbeing Revisited:Introducing the Issue Sara McLanahan (bio) and Isabel Sawhill (bio) Marriage is on the decline. Men and women of the youngest generation are either marrying in their late twenties or not marrying at all. Childbearing has also been postponed, but not as much as marriage. The result is that a growing proportion of children are born to unmarried parents—roughly 40 percent in recent years, and over 50 percent for children born to women under 30. Many unmarried parents are cohabiting when their child is born. Indeed, almost all of the increase in nonmarital childbearing during the past two decades has occurred to cohabiting rather than single mothers.1 But cohabiting unions are very unstable, leading us to use the term “fragile families” to describe them. About half of couples who are cohabiting at their child’s birth will split by the time the child is five. Many of these young parents will go on to form new relationships and to have additional children with new partners. The consequences of this instability for children are not good. Research increasingly shows that family instability undermines parents’ investments in their children, affecting the children’s cognitive and social-emotional development in ways that constrain their life chances.2 Previous Research With these trends as background, the Future of Children first addressed the issue of marriage and its effects on children a decade ago, in 2005. Then, we found that children raised in single-parent families didn’t fare as well as those raised in twoparent families, that the rise of single parenthood was contributing to higher rates of poverty, and that children raised by same-sex couples fared no better or worse than those raised by opposite-sex parents (this last conclusion was tentative, given the lack of good research at the time). The issue went on to consider a variety of ways that government policy might encourage marriage or enhance the quality of parents’ relationships. Marriage education programs promoted and funded by the Bush administration received special attention, although at the time there were no findings from strong evaluations to tell us what those programs might have [End Page 3] accomplished. We also reviewed financial incentives in tax and benefit programs and found that they create some penalties for marriage, although the effect of those penalties on behavior and the feasibility of altering them, given the budgetary costs, were unclear. After reviewing the evidence, the editors concluded that marriage was important for child wellbeing but that policymakers shouldn’t focus on marriage to the exclusion of other strategies aimed at the same goal, such as alleviating poverty, reducing unintended pregnancies, and encouraging fathers’ monetary and emotional involvement. A Decade of Change Although many of the findings and conclusions of the earlier issue remain relevant, the past decade has produced a number of developments and research findings that made it worthwhile to revisit marriage and child wellbeing. Whereas most scholars now agree that children raised by two biological parents in a stable marriage do better than children in other family forms across a wide range of outcomes, there is less consensus about why. Is it the quality of parenting? Is it the availability of additional resources (time and money)? Or is it just that married parents have different attributes than those who aren’t married? Thus a major theme we address in this issue is why marriage matters for child wellbeing. Although definitive answers to these questions continue to elude the research community, we’ve seen a growing appreciation of how these factors interact, and all of them appear to be involved. While marriage is declining, new forms of partnership are emerging, giving rise to a second theme of this issue. The number of cohabiting parents with children, for example, has increased dramatically during the past two decades. How should we view these partnerships? Are they just marriages without a piece of paper, or are they something else? We know that such relationships are, on average, less stable or durable than marriage, and they seem to entail less commitment. But cohabitation can be short- or long-term; it can be a precursor to marriage or to single...