Metabolism, the best-known Japanese architectural philosophy of the 20th century, was an avant-garde design movement whose emergence and dissemination spanned the 1960s. Driven by a core of young architects and writers, Metabolist theorists addressed the particular challenges facing Japan in the early 1960s - rapid, sometimes heedless economic growth and post-war reconstruction that raised questions around permanence and change in architecture and urban design.

While architects in Japan had been grappling with these questions throughout the 1950s, it was the 1960 Tokyo World Design Conference that brought the Metabolists together. Kenzo Tange, the best-known Japanese architect of the era, saw the Conference as a chance to showcase Japanese design to an international audience. In aid of this, architectural critic Noboru Kawazoe collaborated with a group of young architects that included Kiyonori Kikutake, Fumihiko Maki, Masato Otaka and Kisho Kurokawa. Together they published a pamphlet, Metabolism/1960, that collected their varied ideas under the conceptual umbrella of Metabolism. Fundamentally, Metabolism was a biological metaphor at urban and architectural scales - the Metabolists shared a conviction that both cities and individual buildings should use advanced technology to grow flexibly and organically in support of human wellbeing. Architecturally, their designs often featured large-scale fixed ‘backbones’ of infrastructure, designed to support lightweight, movable or temporary additions.

The speculative schemes of the Metabolists were never implemented in their most amibitious forms, but were a key influence on Japanese architecture in the 1960s and beyond. Kurokawa’s Nakagin Capsule Tower was the best-known built example, but Expo 70 was perhaps a better expression of Metabolist ideas. Kurokawa’s Takara Beautilion, Sachio Otani’s Sumitomo Pavilion and Tange’s megastructural Festival Plaza space frame roof all embodied various elements of Metabolist thinking. Kiyonori Kikutake’s Aquapolis, built for the Okinawa Ocean Expo in 1975, called back to his 1959 Marine City proposal and was a late built example of explicitly Metabolist architecture.

Robin Boyd profiled all of the key Metabolist architects in New Directions, and had an ongoing relationship with both Kenzo Tange and Kiyonori Kikutake. In 1975, Kikutake sent a Seasons Greetings card to Patricia Boyd that featured a photo of his Okinawa Aquapolis megastructure.