Realism in the art of the 20th century is striking for its diversity. Although not bound together stylistically or by a "manifesto" of intention, a common thread in realist art is a commitment to the modern world and to things as they appear, whether it be the domestic claustrophobia depicted in Sickert's "Ennui" or the social observation of urban nightlife in Weimar Germany in the work of Christian Shad and Georg Schrimpf. The author examines the so-called "socialist reform" of Stalin's Soviet Union and the condemnation of artists and works not conforming to the academic-realist scruples of Adolf Hitler. With the triumph of abstract expressionism in the 1950s, realism may have been thought outmoded, but its varied and vibrant quality was to be revealed in the "Pop Art" backlash in the United States and Britain, in the work of David Hockney, Richard Hamilton and Andy Warhol. The development of photography in both war and peacetime is also discussed.