I am a professional 4-Wheel Drive Instructor and this is the number one book I recommend to my clients. I cannot say enough about this book. Whether you are a beginner or a trail-hardened expert, this book offers something for everyone at every level. It is down-to-earth, easy to read, thorough, and applicable to all types of four-wheel-drive vehicles and terrain. As your skills and experience increase, you can go back to this book and glean more than you did the last time you read it. Even if your 4-wheel-drive is a push-button-do-everything-for-you variety, you will at least be able to understand WHAT your vehicle is doing FOR you.The author's style is professional, yet personal; thorough, without putting you to sleep; respectful of trails, vehicles and other wheelers, without being preachy. Very helpful and descriptive charts, diagrams, and photos.My only complaint is that Jim did not write this book sooner!