In recent years there has been a rapid growth in the number of households headed by women and in the proportion of these households receiving public assistance. This paper presents a model to test the hypothesis that changes in the public assistance system contributed to the increase in these households. Current Population Survey data on the number of women in various household status categories are analyzed. Major findings include: (1) most of the increase in female-headed households was accounted for by childless women who are generally ineligible for public assistance benefits; (2) although the public assistance system has become more generous in recent years, a married woman who becomes a female head can expect a substantial drop in her level of economic well-being. (Author)