I read with interest the review from the "professional" cockatiel person. What seems to be a 'one star' for them happens to be very useful to all of us "non-professionals".This book has helped beginners and that is what counts. Sometimes, the "experts" are dead wrong when it comes to the simpleness of a book helping the beginning cockatiel owner. This isn't bad, because most of us could give a hoot about genetics and showing your cockatiel at contests.Good book for beginners.