U.K. were a British progressive rock supergroup originally active from 1977 to 1980. The band was founded by bass guitarist John Wetton and drummer Bill Bruford, formerly the rhythm section of King Crimson. The band was rounded out by violinist/keyboardist Eddie Jobson, and guitarist Allan Holdsworth. Bruford and Holdsworth left in 1978, and Bruford was replaced by drummer Terry Bozzio. Jobson, Wetton and Bozzio reformed U.K. for a world tour in 2012.

John Kenneth Wetton was an English musician, singer and songwriter. Although he was left handed he was known as a dexterous right handed bass player and had a booming baritone voice Wetton joined the band Family in 1971 for a short time before joining King Crimson in 1972. After the breakup of King Crimson at the end of 1974, Wetton spent the next seven years as a member of other progressive rock and hard rock bands which included Roxy Music (1974–1975), Uriah Heep (1975–1976), U.K. (1977–1980) and Wishbone Ash (1980–1981).