World So-Kyokushin is founded by, and under the leadership of Hanshi Daigo Oishi. Who is a direct student of Sosai Mas Oyama and who became Sosai’s uchi-deshi. The organization was formed in response of the splitting of Kyokushin Karate into various groups. It aims to keep the pure essence of Sosai Mas Oyama original style intact.

So-Kyokushin focuses on Kyokushin as a Budō (way of life), emphasizing complete training that includes realistic self-defence, kata and kumite. It underlines the importance of consistent and concentrated repitition.

The organization was also created to combat the rise of groups taking advantage of the Kyokushin name without possessing genuine qualifications as a Shihan or Sensei, while they aim to provide quality instruction. World So-Kyokushin is a globally present international organization, organizing seminars and events for practitioners from various countries.