A small book based on lectures given by one of the masters of modern algebra. This very brief but amazingly clear book reads very easy and comfortable. In this book Galois theory is exposed in a modern way, with the term formulation of the theory of bodies and their extension. If one complements the reading of this book with the same title written by HM Edwards (Springer GTM), we get to see the connection between certain fundamental concepts of modern abstract agèbre and historical motivations that are the basis of its developments . In short, for the price (thank you in Dover editions), I recommend it to all lovers of the beautiful mathematical theories have always in the pocket or in a corner of their personal biblithèque.