We would like to express our thanks to all of those involved in the original Chapel Hill conference (or their estates) who very kindly gave their permission to reproduce their papers and comments, without which this book would not have been possible. We would also like to thank those involved in the smooth, speedy publication of the book, especially Beatrice Gabriel for her excellent proof reading.
DR is grateful to the the Dolph Briscoe Center for American History at the University of Texas at Austin for allowing him access to the Bryce DeWitt Papers; to Cécile DeWitt, firstly for allowing access to her own archive of papers and letters, from which much of the historical material in the introductory chapter was drawn, but also for allowing me to take part in this wonderful project; to Jürgen Renn, Max Planck Institute for the History of Science, and Don Salisbury, Austin College, for some much needed motivation, resulting in a significant speed up in the book's production; and to the Australian Research Council for their generous support of the History of Quantum Gravity Project (DP0984930) that the present book contributes to; and to the Max Planck Institute for the History of Science for hosting me as a visiting fellow during the books's completion. Finally, DR would like to thank his wife, Kirsty, and children, Sophie and Gaia, for putting up with his very many absences while this work was being completed.