During the same time period, Lewis held various other positions as well, including head of faculty for the summer sessions held at the Lenox School of Jazz in Lenox, Massachusetts from 1957 to 1960, director of the annual Monterey Jazz Festival in California from 1958 to 1983, and its musical consultant, and "he formed the cooperative big band Orchestra U.S.A., which performed and recorded Third Stream compositions (1962–65)". Orchestra U.S.A., along with all of Lewis's compositions in general, were very influential in developing "Third Stream" music, which was largely defined by the interweave between classical and jazz traditions. He also formed the Jazz and Classical Music Society in 1955, which hosted concerts in Town Hall in New York City that assisted in this new genre of classically influenced jazz to increase in popularity. Furthermore, Lewis was also commissioned to compose the score to the 1957 film "Sait-On Jamais", and his later film work included the scores to "Odds Against Tomorrow" (1959), "A Milanese Story" (1962), Derek Jarman's version of "The Tempest" (1979), and the TV movie "" (1994). His score to "Odds Against Tomorrow" was released on both an original soundtrack album (UA 5061) and an interpretation album by the MJQ in 1959.