It occupies a four-floor, 55,000 square-foot facility in a wing of the Simon Music Center.

[1] Many such collections are housed within the library's climate-controlled vault and are accessible upon request.

The collection grew from a few scores and books in Campbell's office into one of the largest music libraries in the world, holding hundreds of thousands of physical books, scores and recordings, in addition to providing access to numerous online databases.

[2] In 1939, the university hired its first full-time music librarian, Ethel Louise Lyman.

By the time she retired in 1960, the collection included 35,000 books, 12,000 recordings, and over 137,000 pieces of printed music.