Very insightful, clear, and non-technical. I've recommended it to parents and pediatricians. Even though each of the ideas presented is not 100% proven, developmental psychology usually is not. Many are compelling and this book changed my outlook on many aspects of child rearing and education.
I don't have any children of my own but I'm going out with a woman who has two teenage girls (11 and 13). Being the only guy in the household and always seeking to understand better the dynamics between boys and girls I found this book very very helpful and insightful.
I highly recommend this book to anyone who is having to raise or deal with young people in today's society.