This is a synthetic collection consisting of manuscripts and typescripts, notebooks from 1909 to 1912 and 1935, correspondence, financial and legal documents, and portraits of the author. The collection also includes manuscripts and typescripts, diaries for the years 1911 to 1917, and legal documents relating to the author from various individuals, including her sister Kathleen Millay many of whose papers are also in the Berg Collection. The correspondence, dating from 1909 to 1950, includes letters, postcards, and telegrams to Kathleen Millay, Frances Shapli, John Hall Wheelock, Harper & Brothers publishers, and others. Also present are letters relating to the author, dating from 1917 to 1974, between various correspondents, including her husband Eugen Jan Boissevain, Arthur Davison Ficke, Ralph Fitzwater, Autti James, W. Somerset Maugham, Kathleen Millay, Norma Millay, Vincent Sheean, Robert Penn Warren, Edmund Wilson, Harper & Brothers publishers, and others. There are letters to Millay from Frank Altschul, Kathleen Millay, Henry Tolman Millay, and others, dating from 1916 to 1952.