Many thanks to those who helped in the preparation of this book. We thank our technical reviewers: Bill Murray, Michael Shaff, Danny Smith, Tim Townsend, Wietse Venema, John Viega, Paul Vixie, and Yvonne Wilson. We must also recognize our editor, Debby Russell. Her substantial previous experience with this subject made her expert assistance all the more valuable. Thanks as well to the entire O'Reilly production crew. It is only fair, too, that we thank AT&T Long Distance for their "AT&T Unlimited" calling plan. Coauthoring this book with some 2500 miles of separation between the authors, even with all of the connectivity of the Internet, has been so much easier knowing that we could call each other so easily and quickly, without the worry of paying our mortgages.

From Mark: First, I would like to thank Tim Townsend of Sun Microsystems for his unrelenting intellectual honesty in pursuing the secrets of enterprise security and for taking me along on part of his journey. I owe a debt, too, to Gene Spafford, for his help some years back in thinking through many of the social and business issues that surfaced later in this book.

I also need to acknowledge my friend and coauthor Ken van Wyk. It was his unique blend of expertise, talent, discipline, good humor, and patience that made this impossible book possible again.

Lastly, I owe a special thanks to my wife Paula and our youngsters, who have made so many small sacrifices (and a few large ones) in order to allow me to get all this off my chest.

From Ken: Thanks first to my coauthor and dear friend, Mark Graff, for inviting me to help with the project that he started. Although I have written a good share of software, I've never been a professional developer; I have, however, spent countless hours analyzing attacks and software flaws. Thank you, Mark, for believing in me and for letting me add my share of engineering flavor to this book?from the bridge on the cover to following a development lifecycle flow through the organization of the chapters. It's been an amazing collaborative effort that's been a learning experience for me from day zero.

Thanks, too, to my boss for over ten years (and numerous employers) Mike Higgins. Thanks for all of your leadership, patience, friendship, and support?and for the positive energy that comes from sharing a birth date with a coworker.

Lastly, thanks to my wife Caren, to our two glorious basset hounds Beau Diddley and Sugar Magnolia, and to all of my family and friends who have provided the moral support and enthusiasm to help me keep going.