William Gurstelle is the author of the best-selling 'Backyard Ballistics'. He is also a professional engineer and a technogeek robot builder. Gurstelle and his sons build and compete in the growing number of regional competitions with their own Tosca and Weber the Grillbot. He lives in Minneapolis, Minnesota.

"You know that one book you're allowed to have on a desert island? Take this. You'll need it, if you're going to defend it!" -- Ziya Tong, host, Daily Planet

"Ever feared that raging Viking or Mongol invaders are about to attack your home? Gurstelle eases those concerns with a perfect blend of history and how-to, from building a battering ram-proof door and a house-surrounding moat, to making an updated version of Da Vinci's catapult. I haven't felt this safe, or productive, in centuries." -- Mike Senese, Executive Editor, MAKE

"Some designs lend themselves to science projects and would appeal to high school students as well as general readers. Practicality aside though, this book is a delight... readers will learn some military history while having a good time." -- Library Journal

"A fascinating journey for historians and makers alike. Neither of these elements are too focused on, leading to a very balanced and fun read." --FactoryTwoFour

"Gurstelle has done the research, so it isn't just the engineering but the history behind it that you take away... That's what separates this from a doomsday prepper's guidebook." --DoItYourself.com