The papers of Roger Sessions are divided into two main groups by the fact that some are bound (volumes) and some are unbound (boxes). Within these two groups, the papers have been arranged first by genre (cantatas, concertos, exercises and studies, opera, quartets, sonatas, symphonies, miscellaneous musical works, prose works, correspondence & photographs, and papers of others); then by the titles of the individual works; finally, in a sort of rough chronological order, so that sketches fall before completed works, folders marked "1938-1956" come before folders marked "1939-1956," and so on.

Separate lists are available for the contents of the bound material (volumes 1-23), the unbound material (boxes 1-13), and additional unbound material (boxes 14-17). If you know what you are looking for, the best place to look is in the Index to all of the previous lists, which starts on page 9. Wherever feasible, Sessions' original organization of the material has been kept intact, and the folders are as he marked them.

In the Index, two double-digit numbers separated by a slash (e.g. 01/01) indicate a box and folder number (in the above example, Box 1, Folder 1). Ordinary numbers, such as 5 or 23 (in bold), refer to the numbers of bound volumes. The interval 04/06 - 05/02 includes the folder 4.5/01, an oversized folder in Box 4.5 which contains sketches of Quartet No. 2.