Preparing Your Dog For Obedience Trails Book by Adele Yunck ©2008 Destined to part of your training bag, this handy guide has lots of tips and ideas for using proofs to challenge your dog’s understanding of an exercise. During proofing, you expose your dog to more and more difficult distractions to teach him to maintain his concentration and complete the obedience exercises. For everyone who has ever said “but he’s never done that before…” at an obedience trail, this book is for you! 151 pages, 51⁄2" x 81⁄2", spiralbound—with 145 photos and illustrations.