The collection includes correspondence, photographs, genealogical data, diaries, programs, clippings, legal and financial papers, and memorabilia of Nelson P. Darling and his son Frank Nelson Darling. There are letters from Billie Burke, Anton Long, Gustav C. Luders, Leopold Stokowski, and Florenz Ziegfield.

The collection consists of correspondence, documents, clippings, music programs, photographs, scrapbooks, and memorabilia relating to the musical career of Hermann Dossenbach. Also present in the collection is Dossenbach's masonic Corinthian Temple Lodge pin.

The William Hobart Mitchell Papers are comprised of five series: Correspondence, Music Career, Writings, Personal Papers and Teaching Materials. The largest body of correspondence contains letters written between Mitchell and his first wife, Claramary (Clerky), that document their courtship in the mid 1930s as well as William's time in the Civilian Public Service unit during World War II. The majority of the letters relate to William's musical tours of universities and colleges throughout the United States between the late 1940s and the early 1960s. This group of letters shares William's experiences during his travels as well as documenting Claramary's everyday life in New York City and later in Rye, New York.