Jeet Kune Do (截拳道 in pinyin: jié quán daò; in Jyutping: zit6 kyun4 dou3; literal meaning: "Way of the Intercepting Fist"), also Jeet Kun Do or JKD, is the system based primarily on a few styles of Chinese martial arts and developed by Bruce Lee.

This eclectic system combines techniques taken from some other martial arts; the trapping and short-range punches of Wing Chun, the kicks of northern kung fu styles as well as Savate, some footwork found in Fencing and the techniques of Western Boxing, among others. It should be noted that JKD is not a hybrid system, rather, it is Bruce Lee's personal interpretation of the martial arts. Bruce Lee stated that his concept is not an "adding to" of more and more things on top of each other to form a system, but rather, a winnowing out. It can be compared to a sculptor carving the unnecessary elements from a block of material, until he has the form he wants. That is the image that Lee wanted to use to describe JKD.

Jeet Kune Do is what was left at the time of Bruce Lee's death. It is the culmination of the life-long martial art development process Lee went through. JKD was heavily influenced by Western Boxing and Fencing (Bruce gave up on the more traditional Wing Chun elements because he felt that they were only good at medium range, not at long range, where he claimed real fights often start), the result was that Bruce stopped using many of the Wing Chun stances he had learned in favor of what he claimed were more fluid, flexible Western fencing and boxing stances. The claim is that allowed him to "flow", not to be stuck in stances, a positioning that Lee believed was a feature of some of traditional Wing Chun that he dismissed as the "classic mess". Some people however, believe that Lee did not totally give up Wing Chun in JKD. (Dan Inosanto once said that originally, Bruce Lee wanted to create the ultimate fighting form, but later in the development of JKD, he wanted to use the art for personal development, not just to become a better fighter.

JKD not only combines some aspects of different styles, it also simplifies many of those aspects that it adopts. For example, Bruce Lee almost always chose to put his power hand in the "lead," with his weaker hand back, therefore he almost always used the right hand stance of Wing Chun in JKD and discarded the left hand and center stance. This is not the case in all modern branches of JKD, some follow the favored left hand forward stance of western Boxing. Critics say those simplifications change what was adopted into something else, and the "adoptions" should no longer be credited to the original arts.

Lee emphasized what he believed to be the combat effectiveness of JKD, and did not stress the memorization of kata (型), taolu (套路, tào lù) or quan (拳, quán, the same word as the kune in Jeet Kune Do) solo training forms the way that most traditional styles do in their beginning level training. While practicing Western wrestling moves, Lee was once pinned by a skillful opponent, who asked what Lee would do if he actually found himself in this situation. Lee replied, "Well, I'd bite you, of course." The JKD theory being that a fighter should do whatever is necessary to defend him or herself. Lee's goal in JKD was to break down what he claimed were limiting factors in the training of the traditional styles, and seek a fighting art which he believed could only be found in the event of a fight. JKD is nowadays seen as the first of the modern spate of mixed martial arts.

JKD followers claim that it is not a fighting style so much as a fighting philosophy. What JKD practitioners describe as the weakness of traditional martial arts is its "rote memorization" disciplines. They claim that these memorized movements will not be of help in an actual street fight. JKD does not make one a good fighter, they claim, it makes one a better fighter.

Bruce Lee's comments and methods are seen as controversial. Many teachers from traditional schools disagree with his opinions on these issues, especially seeing what Lee described as their lack of strategic flexibility due to "rote" teaching methods to be a misunderstanding on Lee's part. Most, if not all, traditional martial arts teachers say "fluid" strategy is a feature of martial training that is indeed addressed in the curricula of most traditional styles at advanced levels, when the students are ready. The schools Lee criticized tend to see their initial conservatism as a safety feature; a legacy of practical experience passed down from generation to generation, said to ensure that their students are thoroughly prepared for advanced martial training, skipping nothing and developing intangibles such as good character, patience and discipline. The hierarchy of the traditional schools is said by this reasoning to provide a level playing field for all students by instilling respect and care for one's seniors, peers and juniors, so that everyone, not just the physically gifted, has an opportunity to benefit from the training provided in a martial art school.

JKD Branches

Although Bruce Lee officially closed his schools two years before his death, he allowed private teaching by his then current instuctors. Since Bruce Lee's death, JKD has fractured into different groups by way of legal and personality conflicts. The main division can be split into two major branches:

• The Original/Jun Fan JKD branch, whose main proponents are Taky Kimura , Ted Wong, Tim Tackett and Lamar Davis II , teaches only what Bruce Lee taught, and leaves individual development of the art beyond this framework to the individual student;

• The JKD Concepts branch, whose main proponents are Dan Inosanto, Larry Hartsell , Paul Vunak and Burton Richardson, have continued to develop JKD, under the philosophy that it was never meant to be a static art but an ongoing evolution. This branch has incorporated elements of Kali, silat, Gracie jiu-jitsu, and elements from many other martial arts into the main fold of its teachings.