We wish to acknowledge the Robert Wood Johnson Foundation’s Substance Abuse Policy Research Program for generously supporting the collaborative project that is the basis of this volume. The American Legacy Foundation provided additional support for Ronald Bayer’s work. Eric Feldman received funding from the Center for Global Partnership’s Abe Fellowship Program, the Japan Society for the Promotion of Science, and the University of Pennsylvania Law School. We are grateful to John Arras, Marc Galanter, Thomas Murray, Robert Rabin, and Victor Rodwin, who attended numerous project meetings and shared insights that greatly improved the quality of this book. New York University’s Institute for Law and Society helped to administer the project in its early stages, the National Academy of Sciences’ J. Erik Jonsson Center in Woods Hole, Massachusetts, welcomed us to its superb facility for one project meeting, and Ariane Chebel d’Appollonia, along with the staff at the American Centre of Sciences Po in Paris, generously and graciously hosted our final gathering. James Colgrove made innumerable and invaluable contributions to the research project and to this book. Harold Pollack’s thoughtful comments helped us to strengthen the final manuscript, as did feedback from several anonymous reviewers. Finally, we have greatly benefited from Stephen Scher’s careful and extended editorial work.