Summary: Elderly unmarried women are much more likely to be living below the poverty line. Twenty-two percent of unmarried elderly women have income below the poverty threshold, compared with 15 percent of unmarried elderly men and only 5 percent of elderly married couples. Under current Social Security law, women tend to receive lower financial benefits than do men, primarily because they usually have lower lifetime earnings and work fewer years. Women's experiences under pension plans also differ from men's not only because of earning differences but also because of differences in investment behavior and longevity. Moreover, public and private pension plans do not offer the same social insurance protections that Social Security does. The Social Security Advisory Council's reform proposals aimed at resolving future financial problems confronting the system contain elements that may exacerbate the differences in benefits. For example, proposals that call for individual retirement accounts will pay benefits that are affected by investment behavior and longevity. Expected changes in women's labor force participation rates and increasing earnings will reduce but probably not eliminate these differences.