Every year, Americans spend around 18 percent of U.S. GDP on health care (including administrative costs) and over $600 million of federal government money on care for those over the age of 65. Yet there are wide regional and even local variations in the treatment of particular ailments, and a good deal of care is provided on the basis of traditional practice rather than scientific evidence of its effectiveness. The United States stands out among rich countries in resisting evidence-based medicine—not in theory, perhaps, but in practice. In this informative book, the authors, all political scientists, document this phenomenon and then consider why ordinary people, physicians, and politicians all resist public spending on research that would produce obvious benefits for everyone. In brief, there is no broad constituency for such programs, yet there is plenty of opposition from the pharmaceutical and other medical industries, which fear that weak evidence for their treatments’ effectiveness will reduce their sales. The medical community (and some segments of the public) also worry that a stricter emphasis on evidence-based approaches would lead to mandated treatments rather than merely better information, and would thus detract from the authority, autonomy, and status accorded to physicians.