I purchased this book about six months ago. I've traveled to Montana in the past to fish, and was planning another trip this summer. While we planned to fish some old, familiar rivers such as the Yellowstone, the Madison and the Gallatin, we also wanted to try some new waters that we hadn't fished before. My wife and I spent time reading the information on the various rivers discussed in the book, and decided to also spend time in the Missoula area. We used the book not only as a tool to decide where we wanted to fish, but we also used the maps to get us where we needed to go. The end result was a successful fishing trip to Rock Creek and the Bitterroot,which was certainly aided by this exceptional book. By the way, the authors are incredible photographers; their photos in the book are great. I recommend that anyone contemplating a fly fishing trip to Montana purchase this book prior to their trip.