It is widely known that the incomes of U.S. families became more unequal during the 1980s. The reasons for this rise, however, are not at all clear. Numerous factors have been implicated including slow growth, rising demand for highly educated workers, and shifts in family structure and family members' work patterns.

This article describes the 1973-94 increase in inequality of family incomes and related shifts in wage inequality, work trends, and family patterns. The author also examines patterns of inequality among the nine Census regions in the United States and differences in their economic and demographic characteristics. She then investigates the relationship between family income inequality and these factors. In brief, changes in both economic factors and family structure have been associated with rising family income inequality over the last two decades, with the increase in single parenthood and the growing wage premium to college education playing key roles. Among regions, part-time work, low labor force participation, and minority population are associated with greater inequality.