We're not too sure what's so "gentle" about having the ability to quickly choke another human being unconcious or quickly break their joints & ligaments at will. Regardless, the so-called "gentle art" of Brazilian Jiu Jitsu (sometimes called Gracie Jiu Jitsu, and other times called "involuntary Yoga") has - since the beginning of the UFC in 1993 - become one of the most popular martial arts around the world. This is due, in part, to its extreme effectiveness inside the octagon, and in self-defense situations. Brazilian Jiu Jitsu ("BJJ") is practiced by itself, as a stand-alone martial art, as well as by mixed martial artists, including most current & past UFC fighters. Just like anything else, not all Jiu Jitsu gyms are created equal. Check out reviews of all Brazilian Jiu Jitsu gyms here at AllGymReviews.com!