For anyone interested in how Foucault's methods were developed or employed, this book is a must read. While often dense (the author could have easily made his arguments using more accessible language), the book follows Foucault's relationship to a number of philosophical movements upon which he himself commented (Kant, Weber, the Frankfurt School), but does so in a way that convincingly and effectively delineates where Foucault differs (and in turn why his methods are so important to philosophy). Taken together with his essays "Nietzsche, history, genealogy" and "What is enlightenment?", as well as Nietzsche's "On the Genealogy of Morals", this book is an indispensable guide to Foucault's methods.