Hoi Jeon Moo Sool is a Korean martial art created by Grandmaster Myung, Jae Ok. Grandmaster Myung has studied the martial arts for more than 40 years. Previous to 1972 Grandmaster Myung was a hapkido practitioner and master. In 1972 Grandmaster Myung officially introduced Hoi Jeon Moo Sool to the world.

While Hoi Jeon Moo Sool is a relatively new martial art, it is based on techniques that have been used throughout the ages. There are only a finite number of ways to manipulate the human body. The real difference between martial arts that utilize joint locks is the manner in which the practitioner enters the joint lock and what they do after the joint lock has been applied. Grandmaster Myung has developed a system utilizing a circular motion for these actions. The use of the circular motion allows smaller individuals move larger attackers with relative ease. There are a total of 3001 different defenses within Hoi Jeon Moo Sool. Also found under the umbrella of the Hoi Jeon Moo Sool World Federation are Jok Sool Do (3200 kicking techniques), Bong Sool Do(986 long stick techniques) and Kum Sool Do(390 sword techniques).

There are now schools located in Asia, Europe, Africa, North America and South America .