Acknowledgments Although our names are on the cover, this book contains relatively little that originated with us, but on the other hand it contains relatively few references. When the first edition of this book was written Game AI wasn't as hot as it is today: it had no textbooks, no canonical body of papers, and few well-established citations for the origins of its wisdom. Game AI is a field where techniques, gotchas, traps, and inspirations are shared more often on the job than in landmark papers. We have drawn the knowledge in this book from a whole web of developers, stretching out from here to all corners of the gaming world. Although they undoubtedly deserve it, we're at a loss how better to acknowledge the contribution of these unacknowledged innovators. There are people with whom we have worked closely who have had a more direct influence on our AI journey. For Ian that includes his PhD supervisor Prof. Aaron Sloman and the team of core AI programmers he worked with at Mindlathe: Marcin Chady, who is credited several times for inventions in this book; Stuart Reynolds; Will Stones; and Ed Davis. For John the list includes his colleagues and former colleagues at AiLive: Brian Cabral, Wolff (Daniel) Dobson, Nigel Duffy, Rob Kay, Yoichiro Kawano, Andy Kempling, Michael McNally, Ron Musick, Rob Powers, Stuart Reynolds (again), Xiaoyuan Tu, Dana Wilkinson, Ian Wright, and Wei Yen.