Over the last 50 years, the United States and other western countries have experienced dramatic and long-term changes in family and household formation, and in the ways individuals and families support themselves economically. The changes are well-known: people are deferring marriage to later ages and choosing not to marry at all; divorce rates are at high levels after rising dramatically and stabilizing; more children are born outside marriage and growing up with only one parent; and the sources of family income have shifted, as the role of men’s earnings has declined while the roles of women’s earnings and government transfer benefits have increased. The trends and patterns vary sharply by educational attainment. More educated women are becoming less likely to divorce and still are very unlikely to bear a child outside marriage, while among less-educated women, the propensity to marry is declining, divorce rates are high and increasing, and nonmarital births have been rising and now account for over half of their births (Ellwood and Jencks 2004; Martin 2006; Raley and Bumpass 2003). Although it is difficult to quantify the impacts of the complex interactions among marriage, employment, fertility, and the functioning of families, the consensus view is that on balance these demographic and economic trends have contributed to child poverty and economic inequality, harmed the health and well-being of adults, and diminished the ability of children to grow into productive and well-functioning adults.