For anyone unfamiliar with what Brazilian Jiu Jitsu is, it is important to understand the proceeding ‘Brazilian’ tag to Brazilian Jiu Jitsu is an Americanized version of what is referred to in the rest of the world simple as Jiu Jitsu.  The term is becoming more and more popular with increased use around the world because of the sports origin to the Brazilian Gracie family.
 
It is also important to understand that the sport of Jiu Jitsu used in tournaments, compare to Jiu Jitsu used for self defense (or Jiu Jitsu for MMA), and differ quite a bit. The sport of Jiu Jitsu focuses on winning points for advancing to dominate positions, and finishing a fight with a submission. While Jiu Jitsu for MMA utilizing a variety of mixed techniques where to focus is self protection and ending a fight as quickly as possible. In general, the rules of sport Jiu Jitsu offer a greater protection to its competitors, and put a higher focus on utilizing leverage over strength. 

In the very early days of Jiu Jitsu seen in MMA, Jiu Jitsu techniques were held in the highest esteem with fighters like Royce Gracie in the UFC, with the ability to finish fights in times never seen before in MMA matches. At that time, very few, if any, UFC fighters had knowledge of ground fighting. As time has passed, the importance of Jiu Jitsu techniques for the overall curriculum of MMA fighters has been held to a very high esteem, and is typically seen now as an essential part of training. 

In regards to the sport of Jiu Jitsu at proper Jiu Jitsu tournaments, popularity within the U.S. has grown to great proportions. Organizations such as IBJJF (International Brazilian Jiu Jitsu Federation), and the ADCC (Abu Dhabi Combat Club), have brought an organized competition setting for those who are training at Jiu Jitsu academies across the country. These organizations also travel the world, and continue to push the popularity of the sport in each corner of the globe.