Sir Tīmoti Samuel Kāretu KNZM QSO CRSNZ (born 29 April 1937) is a New Zealand academic of Māori language and performing arts. He served as the inaugural head of the Department of Māori at the University of Waikato, and rose to the rank of professor. He was the first Māori language commissioner, between 1987 and 1999, and then was executive director of Te Kohanga Reo National Trust from 1993 until 2003. In 2003, he was closely involved in the foundation of , the Institute of Excellence in Māori Language, and served as its executive director.