This collection contains musical scores and parts for songs arranged by American musical arranger Billy May (1916-2004), dating from the late 1930s to early 1970s. There are files for 567 titles from more than 100 different composers including Count Basie, Bob Crosby, Tommy Dorsey, Duke Ellington, Benny Goodman, Harry James, Glenn Miller, and Henry Mancini. For each title, there is typically a holograph score showing all of the parts for different instruments and holograph sheet music for individual instruments. The music includes popular songs, Big Band and Swing, jazz, Latin music, and music for television and movies.

Housed with the collection in Box 1 are some photocopies of Mays' arrangements and "As you remember them: volume 2" (1972) a Time-Life vinyl record set. It is unclear if the record was received with the collection or added later.