Subseries 1, Books, contains materials pertaining to Zabel's book-length works, The Art of Ruth Draper, Craft and Character in Modern Fiction, Literary Opinion in America, and a textbook, Literature of the United States (translated into Portuguese and French), developed by Zabel from lectures given while teaching in Brazil. Note that various versions of Literary Opinion in America were numbered as they were filed, and not chronologically as it is unclear which versions make up the 1st and 2nd editions.

Subseries 2, Subject Files, is comprised of manuscript material written by Zabel, including book introductions, articles, book reviews, and notes, arranged by subject. Zabel wrote repeatedly about favorite authors and often repurposed material from articles in speeches and books. Subseries 3, Miscellaneous, consists of various articles, book reviews, poetry, speeches, college coursework and teaching materials.