Absolutely brilliant book. I read this just when my partner and I were having major problems and were considering giving it all up. This book really helped me to actually understand why I was reacting to him the way I was, and why we found it so hard to get across to each other what we were trying so hard to explain, but it never seemed to come out quite right! The book is clear and well written, with very practical ideas to work on. Some great chapters each for guys and girls. This book would actually help us relate better to friends and family also.
If you are really struggling in a relationship, if you feel you don't understand each other, or you just feel like giving up, I would really recommend you have a go with this book first. It inspires you to have another go, and to give each other a second chance!