Tohei himself retired from the day-to-day business of the Ki-aikido section and then concentrated solely on the Ki-society and further personal development of ki. Notable students Both before and during his position as head instructor at the Hombu Dojo, Tohei instructed many notable aikidoka. Several of these have since made lasting impacts on aikido in general. Among these are (in alphabetical order): Christopher Curtis, 8th Dan, Chief Instructor, Hawaii Ki Federation, Ki Society Advisor, Europe Shizuo Imaizumi, 7th Dan Shin Shin Toitsu Aikido, who founded the independent Shin Budo Kai style of aikido. Harry Kiyoshi Ishisaka, founder of the Orange County Aiki Kai in California in 1964 Roderick Kobayashi, 6th Dan, founder of Seidokan Aikido. Koretoshi Maruyama, former Chief Instructor and President of Ki Society, who has since founded the independent Aikido Yuishinkai style of aikido. Shuji Maruyama, founder of Kokikai Aikido Alan Ruddock, 6th Dan, introduced Aikido to Ireland, founder of the Aiki no Michi. Steven Seagal, 7th Dan, American action movie actor, producer, writer, director and a Blues singer-songwriter. David Shaner, 8th Dan, Chief Instructor, Eastern Ki Federation, Ki Society Advisor, the Eastern Europe/Russia Ki-Aikido Roy Y. Suenaka, 8th Dan, founder of Wadokai Aikido Shinichi Suzuki, 9th Dan, Head Instructor, Maui Ki Aikido Federation Jon Mamoru Takagi, 6th Dan, founder of Arizona Aikikai. Fumio Toyoda, 6th Dan, founder of the Aikido Association of America and Aikido Association International. Death Tohei died at 9:14 AM, Japan time (GMT +9) on May 19, 2011, after two weeks of being admitted in hospital due to a discomfort in his chest which proved to be inflammation in the lungs. Wataru Hatakeyama, of the Ki Society Headquarters, stated "he went to intensive-care unit (ICU) twice and came back to general ward each time with his strength of Ki, however, his heart got weak little by little this morning and he passed away." Books by Koichi Tohei Koichi Tohei: Ki in Daily Life - 4889960716 Oxford University Press, USA Koichi Tohei: The Book of Ki - 0870403796 Japan Publications, Japan Koichi Tohei: Aikido in Daily Life - 0870402218 Japan Publications, Japan Koichi Tohei: Kiatsu - 0870405365 Japan Publications, Japan Koichi Tohei: Ki Sayings - Ki No Kenkyukai, Japan - privately printed Koichi Tohei: This is Aikido - Japan Publications, Japan - out of print Koichi Tohei: What is Aikido? - Rikugei Publishing House, Japan - out of print Koichi Tohei: Aikido: The Arts of