My six year old daughter has been dealing with trich for several months now, and I have read a ton of books and internet sites. Dr. Penzel's book is the most comprehensive and helpful. Despite having only one chapter relating specifically to children, it is an extremely helpful one and the rest of the book is very informative about the disorder in general as well. His suggestions for motivating younger children have been particularly valuable to us. His advice to and compassion for parents of children with trich has been a lifeline for me-whenever I feel hopeless or that I am losing patience I go back and re-read it and it helps me a lot. I can't say this book or anything else has gotten trich under control for us yet (as Dr. Penzel explains, treatment can be difficult with such a young child), but it has definitely given us hope and gone a long way in helping us to cope with the disorder ourselves and not make things worse for our child.
As far as adults go, I don't have trich so I can't really speak to how helpful it would be for adults who do, but I will say that this is the only book I have read that offers lots of actual specific, practical advice in every area from treatment options to medications to diets, supplements and alternative therapies in an non-biased, factually-based manner. It is certainly the only book I have read that lays out a detailed, specific self-treatment plan. I highly recommend this book to anyone struggling with this difficult disorder.