Expo 70 in Osaka was a watershed, in the histories of post-war Japan and of exhibitions. Following the Tokyo Olympics, it substantiated Japan’s reemergence on the international stage of the Cold War world. In time, it also proved a turning point from the productionism of the immediate post-war years to the consumerism of the 1970s and 1980s. Most significant, it confirmed the Japanese state’s embrace of mega-events as a way of implementing the national planning regime, and thereby canalizing development. This chapter explores Expo 70 in detail, situating it in both the post-war reemergence of international exhibitions around the world and the benefits and costs of high economic growth in Japan. It shows how the Expo became a magnet, for intellectuals and creatives, both for and against, and for visitors, who flocked in greater numbers than for any expo before. It also explores in detail how the expo became a media event. Newspapers and TV attested to the implacable but manifold nature of development, which was evident in the ability of the Expo to conjure infrastructure and catalyse demand, even while it accommodated a fractured world, teeming crowds, and intransigent protest.