Akihiko Takahashi is an Associate Professor at DePaul University, where he teaches mathematics and mathematics education. He has over forty years of first-hand experience in TTP, as well as Japanese Lesson Study, and was one of the leading mathematics teachers in Japan. Since the late 1980s, he has continued to serve as both a writer and editor of Japanese mathematics textbook series, including the best-selling mathematics textbook, Atarashii Sannsuu (New Mathematics for Elementary School), published in Japan by Tokyo Shoseki.