K-1 is a Japanese kickboxing promotion based in Tokyo, Japan founded by Kazuyoshi Ishii, a former Kyokushin karate practitioner, and owned by the Fighting and Entertainment Group (FEG), who organize combat sport events in Japan, and around the world, that include events by the mixed martial arts promotion Dream. K-1 combines stand up techniques from Karate, Muay Thai, Taekwondo, Savate, San Shou, Kickboxing, western-style Boxing, and other martial arts.[2] It’s rules are similar to those of kickboxing but they have been simplified to promote exciting matches that may end in a knockout win. K-1’s techniques and unique rules have led some supporters to declare it a sport distinct from Kickboxing while others maintain that it is just a style of kickboxing.

The principal objective of K-1 is to win either by a knockout or by a split or unanimous decision. Victories are usually achieved by kicks to the legs, head or midsection or using traditional boxing punches, such as the jabs, hooks or uppercuts.

The classic defensive boxing stance is rather ineffective against leg kicks, and fighters are more or less forced to constantly move and counterattack. The traditional clinch, often used in boxing, is not allowed, which has led to a very high knockout ratio in the K-1, since the fighters in other stand-up fighting sports often use the clinch to gain time to recover if they have been hit. Clinching is also a big part of traditional Thai Boxing and the lack of this is one of the biggest differences between Thai Boxing and the K-1 rule-system. If you grab an opponent with the intent of using a knee-technique you have to let go after one single blow. In Thai Boxing, the fighters often hold on to each other to continuously use their knees and elbows.

Due to the combination of rules and allowed techniques, the common low kick has time and again proven itself to be one of the most efficient techniques in the K-1 fighter’s arsenal. Boxers who are pitted against good low kickers have become completely pacified during their attempts to enter the K-1 fighting circuit (due to the extreme damage a low kick can deliver to the leg).

The rules themselves are constantly adapting and changing to create a competition which allows for participants of different styles to fight in a fairer manner, although these rules accommodate kickboxing rules as the main basis.