Ex Libris, a New York City based antiquarian establishment that dealt in rare 20th century avant-garde books, periodicals, and archives, operated from 1973-circa 2000, and was founded by Elaine Lustig Cohen (1927- ) and her husband Arthur A. Cohen (1928-1986). Elaine Lustig Cohen is a graphic designer, previously married to the graphic designer Alvin Lustig (1915-1955), who later married her long-time friend Arthur A. Cohen, a scholar, theologian, and author, in 1956.
The Cohen's began collecting avant-garde books and ephemera from antiquarian bookstores and artists in Europe. Ex Libris began when the couple amassed a surplus of material and Arthur placed an ad in the New York Times that said, "send for my list of Dada, Surrealist, Avant-Garde periodicals and ephemera." The inventory of Ex Libris grew to include other movements of modernism including Bauhaus, Futurism, Cubism, De Stijl, German Expressionism, Constructivism, and Fluxus.
Ex Libris published catalogs of their inventory, designed by Elaine, which were sent to libraries and museums all over the world. The catalogs are now collector's items. Exhibitions were organized at Ex Libris that complemented their inventory, and they often loaned material to be included in exhibitions elsewhere.