For over twenty-five years, Mary Reynolds (née Hubachek, 1891–1950) was Marcel Duchamp’s faithful companion and occasional collaborator. After the death of her husband, she settled in Paris in November 1921. Sometime between summer 1923 and early 1924, she hired M.D. to give her French lessons, and their romance commenced soon thereafter. Reynolds learned to bind books in the late 1920s. Over the next two decades, she created some seventy unique and original bookbindings, several based on M.D.’s designs. Despite her intimate relationship with M.D. and her close friendship with the likes of Man Ray, Hélène Hoppenot, Alexander Calder, Constantin Brancusi, Henri-Pierre Roché, Janet Flanner, Virgil Thomson, Gabrielle Buffet-Picabia, and others, little has been written about her. Étant donné Marcel Duchamp is proud to devote our newest volume to Reynolds’s fascinating life and work. The issue opens with an interview with Reynolds’s niece and nephew. It also offers several unpublished letters and texts, including her correspondence with Brancusi and Man Ray as well as excerpts from Roché’s and Hoppenot’s private diaries. The issue also includes studies devoted to M.D.’s role in the donation of Reynolds’s private collection to the Art Institute of Chicago; his work Moonlight over the Bay at Basswood, presented to Reynolds’s brother as a gift in 1953; her and M.D.’s ongoing support of Calder and his work; and Thomson’s 1930 musical portrait of Reynolds. Over 300 photographs and documents, many of them unpublished, illustrate these and the numerous other articles comprising Étant donné Marcel Duchamp no. 8.