I have a serious, serious issue with the methodology of research in this book, probably because I come from the world of academia myself. I'm familiar with a lot of these relationship models... which have failed, too. The book is a little too rosy for me. The takeaway is: any relationship model *can* work, but it doesn't mean it *will* for you or that it's necessarily sustainable. Also, hate Taormino's writing style, but that's a personal thing. Exercises are helpful.
The first few chapters are about myths about open relationships, how to figure out if an open relationship is right for you, and what makes open relationships work. The middle chapters are about different relationship styles, and then the last few chapters are about common challenges, safer sex practices, legal and practical issues, and raising children. I really like that the chapters on different relationship styles include narratives from real people who are in those relationships. There are helpful questions and exercises throughout the book, as well.