This book and its associated example games are copyright © Roger Firth and Sonja Kesserich 2004. Copying and distribution, with or without modification, are permitted in any medium without royalty provided the copyright notice and this notice are preserved. Exceptions to these conditions must be negotiated directly with the authors (roger@firthworks.com and polilla@idecnet.com). This book is offered as-is, without any warranty. The authors assume no liability for errors and omissions in this book, or for damages or loss of revenue resulting from the use of the information contained herein, or the use of any of the software described herein. Inform, the program and its source code, its example games and documentation, are copyright © Graham Nelson 1993—2004.