The Modern Jazz Quartet (MJQ) was composed of Milt 'Bags' Jackson on vibraphone, John Lewis on piano, Percy Heath on bass, and Connie Kay on drums. Milt Jackson and John Lewis were pioneer bebop musicians who had played together in Dizzy Gillespie's 1948 big band. They pursued separate careers before adding Heath and Lewis to form the Modern Jazz Quartet in the 1950s. Noted for its delicate percussion sonorities, innovative jazz forms, and high performance standards, the MJQ was an immensely popular jazz and “third stream” ensemble until its final concerts in the early 1990s.