This paper explores rich and complex implications of Marcel Duchamp's Mile of String which he created for “First Papers of Surrealism,” the Surrealist international exhibition in New York in 1942. Part of a larger project devoted to investigating Duchamp's role in Surrealist exhibitions and his relation to the avant-garde group, this paper focuses on Duchamp's exhibition installation in the 1942 show. Under the title of “générateur-arbitre” Duchamp played an important role as installation and exhibition designer in a series of major Surrealist exhibitions in the 1930's-1960's. The “First Papers of Surrealism” was held by Surrealists who exiled in New York during World War I, and Duchamp created a labyrinthine installation of string for the exhibition, which physically blocked the spectator and optically hindered his or her contemplative view. Unraveling the intricately related meanings of Mile of String as an independent work of art and an installation for a specific exhibition, I examine the work on two levels: frst, how the work was situated in the context of Duchamp's oeuvre, particularly his earlier work employing string or thread; second, how and in what way the installation rendered a critique on Surrealism as a group and an avant-garde movement. More specifically, by exploring the concepts of ‘pataphysics’ and voluntary ‘nomadism’ implicated in Duchamp's work, I suggest that his Mile of String asserted a critical stance against nationalism and collective identity of Surrealism and manifested a radical individualism founded upon what he called the spirit of ‘expatriation.’