Kaoru Ishikawa (石川 馨, Ishikawa Kaoru, July 13, 1915 – April 16, 1989) was a Japanese organizational theorist and a professor in the engineering faculty at the University of Tokyo noted for his quality management innovations. He is considered a key figure in the development of quality initiatives in Japan, particularly the quality circle. He is best known outside Japan for the Ishikawa or cause and effect diagram (also known as the fishbone diagram), often used in the analysis of industrial processes.