When I began intensive treatment for my OCD, my therapist told me I had to read this book before we started the treatment, ERP. That was the best thing she could have ever done. I knew little about OCD over all and absolutley nothing about CBT or ERP. This book explained all that to me in a very easy to understand way. It is a great first book on OCD and OCD treatment to begin with, like OCD 101. Once I started it, I couldn't put it down. There isn't hardly a page in the book that isn't underlined, highlighted, or written in the margins. This book was truly my OCD Bible. It is an excellent book to start with, for learning all the basics and without a doubt, I did so much better in treatment because I read this book and understood what the treatment was and why it works. I also heard Gail Steketee speak at the National OC Conference and got to talk with her as well. She is an extremely knowledgeable in the field and very down to earth.