“… Not everything that is contemporary is experimental. “Experimental” does not just refer to something new — experimental art rather comes from certain experimental methods. In his work Musée d’Art Moderne, Département des Aigles (1968-72) the Belgian artist and poet Marcel Broodthaers investigates a particular form of experimental art. Broodthaers’ fictional museum project provides a good basis for a study of the concept, as the artist has himself repeatedly referred to the experimental quality of his art. Indeed, our starting assumption in this essay is that this work by Broodthaers illustrates in a paradigmatic way central elements of experimentation in contemporary art of the 1960s and 70s. For example, on 16 May 1972 Broodthaers opened a section of a museum entitled The Eagle from the Oligocene to the Present in the Städtischer Kunsthalle in Düsseldorf, signing it with the following words: “Marcel Broodthaers shows an experimental exhibition of his Musée d’Art Moderne, Département des Aigles, Section des Figures”. The first part of this essay examines the experiment in which a museum with altogether twelve sections is declared to be a work of art. The second part then explicates the experiment in which an exhibition is declared to be a work of art. Finally, the third part examines the role of the viewer within Broodthaers’ artistic experiment.