This book is completely worthless! The 5 star reviews were more than likely writen by the author. If you want a book on grappling buy Royler and Renzo Gracie's Jiu Jitsu book or Rigan Machado's book. All I have ever heard about Robert Ferguson is that he is a shameless self promoter. There is no person that I know of called Doug Gracie! Saying that Ferguson helped develop the Gracie family's jiu jitsu is damn near libelous!