Carter, Elliott Cook, Jr., 1908-, American composer, b. New York City. Carter is considered by many to be the most important contemporary American composer. He studied with Walter Piston, E. B. Hill, and Gustav Holst at Harvard and with Nadia Boulanger in Paris (1932-35). Carter's complex mature music is organized into highly intellectualized contrapuntal patterns to which sympathetic listeners attribute great emotional power. He characteristically uses tempo as an element of form, notably in his technique of "metric modulation," his most famous musical innovation. Highlights from an unusually long and prolific musical career include the ballet Pocahontas (1939), a cello and piano sonata (1948), five string quartets (1951, 1958-59, 1973, 1986, 1995), Variations (1953-55) for orchestra, a piano concerto (1966), a concerto for orchestra (1969), A Mirror on Which to Dwell (1976) for soprano and nine players to poems by Elizabeth Bishop, Night Fantasies (1980) for piano, Changes (1983) for guitar, Adagio Tenebroso (1995) for orchestra, the opera What's Next? (1999), and a cello concerto (2001) composed for Yo-Yo Ma.