Many people, too numerous to mention, have given me advice over the years on alternative societies and socialism, and discussed the issues covered in this book with me. I am very grateful to them all and to the great students who have taken my courses on these topics. Thanks to the following who gave me advice on this book or feedback on parts or all of it: Onur Acaroğlu, Sebastian Berg, David Berry, Esra Demirkol Colosio, Aaron Gain, Danë Goodsman, Richard Mangas, Charlie Masquelier, Paul McGuinness, Laura Morosanu, Rafal Soborski, and anonymous referees. Thanks to Shannon Kneis and all at Bristol University Press. Much love to Sally, Katie, Jake, Felix, Brian, and Christina. This book is dedicated to Mim.