Eddie Bravo is in my opinion the next Helio Gracie as far as jiu jitsu goes. Helio took japanese jiu jitsu which used more strength holds and adapted it to his smaller size by using leverage and the gi. Eddie Bravo has taken the Gracie jiu jitsu system and adapted it to mixed martial arts fighting without a gi. When no gi is present you must use other positions and techniques to accomplish similar goals. This book will teach you that system. Beware flexibility is not required to practice some techniques, but most will require a yoga type level of flexibilty. But hey if you wanna throw up crazy arm bars and triangles you must be flexible anyway. The system is great and you are beginning to see it in mma more and more. This is just the next level of jiu jitsu. I am sure more will follow as the sport grows, but for now these are advanced teachings. I want to trow in that my favorite technique is the electric chair. When someone has you in half guard revert to the electric chair and on someone who is not super flexible you will have it won in a suprising way. I recommend this book to anyone who loves the jiu jitsu game or mma.