Tetsuya Sakai is a professor at the Department of Computer Science and Engineering, Waseda University, Japan. He is also an Associate Dean at the IT Strategies Division of Waseda, and a visiting professor at National Institute of Informatics. He joined Toshiba in 1993. He obtained a Ph.D from Waseda in 2000. From 2000 to 2001, he was supervised by the late Karen Sparck Jones at the Computer Laboratory, University of Cambridge. In 2007, he joined a startup as the director of the Natural Language Processing Lab. In 2009, he joined Microsoft Research Asia. He joined the Waseda faculty in 2013. He is an editor-in-chief of the Information Retrieval Journal (Springer), an associate editor of ACM TOIS. He is a general co-chair of NTCIR. He is also a general co-chair of ACM SIGIR 2017.