Book excerpt: Social insurance in the United States--including the Social Security Act of 1935 and the Medicare, Medicaid, and disability insurance programs that were added later--may be the greatest triumph of American domestic policy. But true security has not been achieved. As Michael J. Graetz and Jerry L. Mashaw show in this pathbreaking book, the nation's system of social insurance is riddled with gaps, inefficiencies, and inequities. Even the most popular and successful programs, Medicare and Social Security, face serious financial challenges from the coming retirement of the baby boom generation and the aging of the population. This book challenges the notion that American social insurance must remain inadequate, unaffordable, or both. In sharp contrast to policymakers and analysts who debate only one income security program at a time, Graetz and Mashaw examine social insurance whole to assess its crucial role in providing economic security in a dynamic market economy. They recognize that, notwithstanding a proper emphasis on individual freedom and responsibility, Americans share a common fate that binds them together in a common enterprise. The authors offer us a new vision of the social insurance contract and concrete proposals to make the nation's families more secure without increasing costs.