The Nihon Ki-in (日本棋院), also known as the Japan Go Association, is the main organizational body for Go in Japan, overseeing Japan's professional system and issuing diplomas for amateur dan rankings. It is based in Tokyo. The other major Go association in Japan is Kansai Ki-in. Its innovations include the Oteai system of promotion, time limits in professional games, and the introduction of issuing diplomas to strong amateur players, to affirm their ranks.
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