First of all, I greatly recommend this book to any type of personality. As Susan Cain explains, the introvert-extrovert axis is one of the few (if not the only) concepts every psychologist uses for personality analysis. And, for the most skeptical of you, it is obvious there is no "pure" introvert or "pure" extrovert, those cases would probably be pathological.According to my rating, I loved this book. It took a lot of research, more than I expected, but it validates problems I've had to deal with ever since I was born. I am a known introvert, but also more than that... a pseudo-extrovert, which is someone that spends a lot of energy on a daily basis acting like an extrovert. Now someone might think that it is dishonest of me to do such a thing but it is just a tool i've developed to lead the life I've chosen, to do the things I love (that take a lot of human contact) and interact with the people that matter most to me. Being an introvert comes with some guilt, right from when we were children, thanks to the extrovert ideal that reigns a little all over the globe (with the exception of asian and nordic cultures). While reading Cain's book, and learning more about sociology and myself (because I found myself nodding on every single page and saying 'That's precisely what I feel, but I've never thought about it this way!'), that stingy feeling was put off.When I talked about this book with some extrovert friends of mine, they all reacted the same way - 'You're kidding, right? There are far more introverts than extroverts!'. I'm not saying that isn't true... to you. That's your perception of the world, which tends to differ a lot from the one of introverts. Anyway, scientific knowledge cannot be based on such perceptions, it uses statistics and a great battery of previously validated tests, and they account for one third of the population being introverts, in North America and Europe.All in all, the message of this book - that I absolutely agree with- is pretty simple - there shouldn't be such an ideal modelling every activity in our society, since kindergarten lessons to employment interviews. Every type of personality should be cherished and its best traits nourished and explored. Like Carl Jung superbly put it - 'The meeting of two personalities is like the contact of two chemical substances; if there is any reaction, both are transformed.'