Terrence Mitchell “Terry” Riley (/ˈraɪli/; born June 24, 1935) is an American composer and performing musician associated with the minimalistschool of Western classical music, of which he was a pioneer. His work is deeply influenced by both jazz and Indian classical music, and has utilized innovative tape music techniques and delay systems. He is best known for works such as his 1964 composition In C and 1969 album A Rainbow in Curved Air, both considered landmarks of minimalist music.

Born in Colfax, California in 1935, Riley studied at Shasta College, San Francisco State University, and the San Francisco Conservatory before earning an MA in composition at the University of California, Berkeley, studying with Seymour Shifrin and Robert Erickson. He was involved in the experimental San Francisco Tape Music Center, working with Morton Subotnick, Steve Reich, Pauline Oliveros, and Ramon Sender. His most influential teacher, however, was Pandit Pran Nath (1918–1996), a master of Indian classical voice who also taught La Monte Young and Marian Zazeela. Riley made numerous trips to India over the course of their association to study and to accompany him on tabla, tambura, and voice. Throughout the 1960s he traveled frequently around Europe as well, taking in musical influences and supporting himself by playing in piano bars, until he joined the Mills College faculty in 1971 to teach Indian classical music. He was awarded an Honorary Doctorate Degree in Music at Chapman University in 2007.