As a recently qualified MBTI practitioner I very much looked forward to reading this book, hoping that it would shed light on the history of the MBTI and those who created it, but I was sadly disappointed. The quality of the prose is below average and the author has little or no sense of how to weave facts into a coherent narrative. Katharine and Isabel certainly deserved better. The book serves up a disjointed and seemingly endless litany of Briggs-Myers family trivialities, so much so that most of it reads like a Christmas letter, but it has very little to say about Jung, the development of type theory or the MBTI itself. Don't waste your time with this one.