This book was made possible by the support of the Singapore-MIT GAMBIT Game Lab and Comparative Media Studies at Massachusetts Institute of Technology. Thanks to my colleagues for discussions that have made this book infinitely better than it would have been. Thanks to Doug Sery and the MIT Press for supporting this project. Thanks to Philip Tan, Brennan Young, Jaroslav Švelch, Jonas Heide Smith, Nick Fortugno, Annakaisa Kultima, and Eric Zimmerman for commenting on manuscript parts in their various stages. Special thanks to Susana Tosca, Miguel Sicart, Clara Fernández-Vara, and Jason Scott Begy. Thanks to John Sharp, Nanna Debois Buhl, and Mads Rydahl for 2d illustrations. Thanks for Geoffrey Long for package photographs. Thanks to Gamezebo for collaborating on a survey of their users. Thanks to the developers interviewed: David Amor, Sean Baptiste, Daniel Bernstein, Jacques Exertier, Nick Fortugno, Frank Lantz, Garrett Link, Dave Rohrl, Warren Spector, Margaret Wallace, and Eric Zimmerman. Thanks to the surveyed and interviewed players.