Disability Rights and the American Social Safety Net. By Jennifer L. Erkulwater. Ithaca, NY: Cornell University Press, 2006. 272p. $42.50.

Political scientists who study the American welfare state tend to focus on a small number of social programs. Social Security and “welfare” (now called Temporary Assistance for Needy Families) are probably the best known. Typically, the goal is to show how much one or two factors—for example, public opinion, institutional design, policy elites, race, gender—influence these programs. This book is different. It focuses on two programs for the disabled, Disability Insurance (DI) and Supplemental Security Income (SSI), which are studied less often. And it tries to account for a wide range of influences on their development. The book is a genuine addition to our understanding of U.S. social policy and a fine example of how to create a rich explanation of policy change.