"On 'Mastering The 21 Immutable Principles Of Brazilian Jiu-Jitsu', Paulo Guillobel wears a hat of a scholar and proves that, in more than 26 years of practicing, he has not only trained, taught and competed at high level, but most important of all, has studied the art thoroughly. Every student, teacher and master will surely take advantage of the knowledge carefully organized in this book. This is by far the best Jiu-Jitsu book I ever read." -Luca Atalla, Vice President and Chief Editor of Gracie Magazine Until this book, there has never been a Brazilian Jiu-Jitsu book that has comprehensively explained the most fundamental and unchangeable principles of this martial arts style. Paulo Guillobel's Mastering the 21 Immutable Principles of Brazilian Jiu-Jitsu is a one-of-a-kind book that goes deep into the foundation of the Brazilian Jiu-Jitsu techniques and strategies. With an understanding of the 21 principles revealed in this book, any BJJ student will be able to discover the invisible details behind any technique, and also understand why the techniques are being used.