Cut off from the world for three centuries, the Japan of the Edo period had to compensate for its prohibition of trade through ingenuity, and the scarcity of wood, cotton, and other goods gave rise to a solid culture of recycling that precluded any form of waste. ‘Edonomy,’ as it is called, is a historical circularity model that still has so much to learn from, and in the same spirit the country decided to make its second Expo in Osaka an event that would leave no other legacy than news coverage in media and the recollections of visitors. If in 1970 the future envisioned was one of steel and concrete, the city now hosts an exhibition of sustainable construction where local sugi wood will facilitate full dismantling when the fair ends, letting the isle recover its port function. Hence, in addition to being persuasive showcases, the national pavilions – twelve of which are featured in the next pages – are innovations with intentions of a second life or with a view to reentry of their materials into the production chain.