Tettsū Gikai (徹通義介) is the third spiritual leader of the Sōtō Zen school of Buddhism in Japan. He began his Buddhist life as a student of the Darumashū's Ekan, but later both became students of Eihei Dōgen's newly established Sōtō school. Gikai received dharma transmission from Koun Ejō, Dōgen's successor, and later became the third abbot of the school's head temple, Eihei-ji. Shortly thereafter, he became embroiled in a leadership crisis known as the sandai sōron. Other monks contended that other students, namely Jakuen, Gien or Giin, had stronger claims to the abbacy. The controversy remained unresolved at the time of his death. His abbacy was unpopular with some monks because he introduced innovative practices aimed at making Sōtō more palatable with the Japanese laity, which some claim