Big fan of American Positive Psychology works, it is with great pleasure that I browsed the book that summarizes the theories of the masters in this field. It is easy to read and enjoyable because the author also shares his personal experience. The title, however, is to be taken as a whole since 3 KIFS represent only a chapter of the book. I embarked on its second reading this time taking some notes. I look forward to the next book Florence Servan-Schreiber, on positive psychology or another of his KIFS.