Over the last four decades, American family structures have diversified, women's employment rates have increased, and income inequality has grown. In this dissertation, I analyze the evolving connection between family structure and women's employment and family income, highlighting variations by race/ethnicity and education. I break my analysis into three empirical chapters. The first chapter uses Current Population Survey data to describe associations between family structure and income inequality among American women of childbearing age from 1980-2005 by birth cohort. I consider how women's exposure to different family structures (defined by marriage and children) and the association of family structure with women's family income have changed across cohorts. I show how the economic security associated with marriage and the economic costs associated with motherhood vary across birth cohorts and social groups defined by race/ethnicity and education. Contrary to my hypotheses, I find that the association between income inequality and single motherhood has not changed across cohorts. The other two chapters examine employment differences among women by family structure for population subgroups. In the second analysis, I use Census and American Community Survey data to examine employment patterns of highly educated professional and managerial women by birth cohort. I find that the influence of children on women's employment has decreased across cohorts and that there is no evidence of a new "opt-out revolution." The third analytic chapter maps the employment trajectories of mothers in urban areas in the five years following a birth. Using data from the Fragile Families Study, I test hypotheses about how family structure (married, cohabiting, or living without a partner) influences women's employment. The findings show that controlling for demographic and human capital differences, unmarried women work more than married women. Differences in employment between cohabiting and lone mothers are small. I argue that married mothers have greater economic security and that this accounts for differences in maternal employment by marital status. Taken together, my findings suggest that the influences of family characteristics on women's employment and income are decreasing, reducing inequalities between women of different family structures. However, changes in the distribution of women's employment opportunities and family structures have caused women's inequality by education to increase.