Correspondence, family, business, and personal (1927-1967); artwork, including photographs and reproductions of Martinelli's United Nations commission; statements on his work; and printed material, including clippings about Martinelli (1928-1968), and exhibition announcements, catalogs, and invitations (1934-1968). Correspondents include Aldo John Casanova, Ed Colker, Martin Craig, Dorothy Dehner, Helmut von Erffa, Giannetto Fieschi, Horace Gregory, Peter Grippe, Edmund Haines, Stanley Hayter, Louis I. Kahn, Leon Kelly, Leon Kroll, Norman Lewis, Sam Maitin, Barbara Brooks Morgan, Marnie Pomeroy, Melville Price, Walter Reinsel, Theodore Roszak, Charles Seide, Helena Simkhovitch, David Smith, and Carl Zigrosser.