Original K-1 Grand Prix was a single event tournament held in Japan where competitors participated on invitation. By 1998, K-1 introduced the K-1 World Grand Prix format composed of K-1 Regional Elimination Tournaments (theoretically amounting to six), which qualify fighters for the K-1 World Grand Prix Final. The K-1 in Japan basically established Kickboxing on a mainstream platform where lucrative prize money could be won. Since the downturn of K-1 there have been many other promotions to adopt the kickboxing rule set they created, with a few modifications in each promotion. The Thai fighters have maintained dominance throughout the various organizations over the last 2 decades. Fighters such as Buakaw, Sittichai, Superbon Banchamek, Petchpanomrung kiatmoo9, Yodsanklai, Kaew Fairtex, Yodwicha, have all gone on to have great success in kickboxing through many organisations and Muay Thai remains a dominant force in combat sports.