The collection consists of Keeley's early writings as a student (Princeton, Class of 1948); bound and loose drafts and galleys of novels; short fiction; nonfiction books; articles, essays, introductions, and reviews; awards and speeches; translations of modern Greek poetry; and works edited by Keeley. The writings include the following titles: The Libation (1958), The Gold-hatted Lover (1961), Modern Greek Poetry (1983), School for Pagan Lovers (1993); translations of C. P. Cavafy's Passions and Ancient Days (1971) and Collected Poems (1975), Giannēs Ritsos' Ritsos in Parentheses (1979–the only time these poems were published), and Odysseus Elytēs' Selected Poems (1981). There is literary, academic, organizational, and personal correspondence with internationally-known colleagues and personal friends, such as R. P. Blackmur, Babette Deutsch, Kimon Friar, Carolyn Kiser, William Meredith, W. S. Merwin, Joyce Carol Oates, Giannēs Ritsos, George Seferis, Angelos Sikelianos, Wallace Stegner, Charles Scribner, and Willard Thorp; and with organizations such as the American Farm School, the Modern Greek Studies Association, and the Poetry Society of America, as well as many others.

Faculty material includes translation workshops Keeley taught at Columbia, Princeton, and the State University of Iowa; alumni, committee, and interdepartmental correspondence within various programs at Princeton; and student papers, course outlines, lecture notes, course-related forms, and computerized student grades. The P.E.N. American Center files primarily reflect the years of Keeley's presidency (1992-1993), but span from 1969 to 1990 and include his membership on the executive board in 1980. They include board meeting minutes, memos, correspondence, and P.E.N. international congress material. Also included are Keeley's scrapbook items, miscellaneous notes, manuscripts of translations by others, audiotapes of music by Mikis Theodorakis and readings of poems by Giannēs Ritsos, as well as printed matter.

Additional papers that were acquired from Keeley after his original gift are arranged by accession in Series 10 and 11 and include additional writings, correspondence, faculty papers, P.E.N. American Center materials, family papers, personal documents, memorabilia, photographs, and other materials that compliment many of the existing series. These additions include materials related to Albanian Journal, the Road to Elbasan, Borderlines, A Memoir, "The Grand Tour" (unpublished), On Translation: Reflections and Conversations, The Salonika Bay Murder, Cold War Politics and the Polk Affair, School for Pagan Lovers, and Some Wine for Remembrance, translations of Greek poets, and anthologies Keeley edited, including A Century of Greek Poetry, 1900-2000 and W. W. Norton's The Greek Poets: Homer to the Present.