Option Studio
Spring 2026
Jimbocho, Tokyo
Mohsen Mostafavi

Jimbocho is Tokyo’s one-stop destination for used books. Amidst Tokyo’s model of constant rebuilding, growing competition from online shopping and an aging returning customer base, mega-corporations planning large-scale redevelopment projects threaten to transform neighbourhoods like this one into the next Azabudai Hills. This studio proposes alternatives for Jimbocho that rely on re-use, re-programming and tactical urbanism while maintaining the culture and vitality of its booksellers. Like many of Tokyo’s major streets, Jimbocho’s Yasukuni-dori is designed to propel heavy foot traffic from end to end. The speed of this thoroughfare often contradicts the neighbourhood’s leisurely browsing, and because Tokyo has few true public spaces, giant shopping hubs absorb the slow-paced functions of the city.

One Japanese mother mentioned that it was difficult for her to come to Jimbocho because there was nowhere to leave her children while browsing books. Indeed, Tokyo’s playground infrastructure is frequently undersized and sandwiched between tall buildings—children deserve open space away from pedestrian highways to roam and explore, but this office-filled neighbourhood offers none.

Jimbocho is in need of a public space that can accommodate family outings, community events, and people who just want to read sitting down. This project has two ambitions: to foster a Jimbocho accessible for all ages, and to repurpose existing office buildings as degrowth shifts demand.

RETROFIT AMID DEGROWTH: Japan’s shifting demographics mean the city must be prepared to build less, not more; as Jimbocho’s aging office buildings built with short lifespans struggle to keep tenants, this project proposes a radical alternative to demolition—a new “public ground” at the roof level of existing buildings that attracts new program to the neighbourhood. This strategy brings Tokyo residents up to this open plaza level, which dissolves into small stalls repurposed from the top levels of office buildings. Large, scenic plazas reactivate and connect small, disjointed spaces from the top down. In this “partial re-use” approach, each building individually negotiates its participation and transitions flexibly without compromising existing tenants. Vertical cores and structure for the roof level stand independently but provide direct ground access and additional circulation to repurposed spaces. On the lower levels, platforms connecting repurposed buildings hold public functions: gathering, reading, observing, exercising and relaxing. For parents, these spaces offer continuously changing activities and events as well as permanent stalls. For children, an expansive and continuous playscape stretches above at the roof level—without boundaries or instructions, children can safely run wild.

JIMBOCHO FOR ALL AGES: Van Eyck and Noguchi argued that playgrounds should offer abstract, open-ended sculptural forms that stimulate children’s imagination and self-directed exploration, rather than prescriptive equipment. In Tokyo’s urban setting of choreographed motion, there are few spaces within the city where children feel a sense of discovery and ownership of the conditions of play. Here, under safe supervision and separated from the Tokyo street bustle, children can find wilderness in the heart of the city. Open space encourages creativity, movement, social interaction and physical exertion, replacing static slides and swings designed to be enjoyed individually in confined areas. Each element in the playground is routinely changed, moved and reconfigured to produce a fresh experience every time.

The rooftop playground encourages contact with nature by placing equipment among diverse greenscapes, and on Jimbocho’s Yasukuni-dori, circulation cores expose vertical greenhouses that bring rare greenery down to the street level while inviting pedestrians up to the new public ground.

There is space for parents to play, too—parents can watch their children from a central lounge area in the playground, or enjoy activities for Tokyo residents of all ages at the lower levels. The forest-like structural system at the playground level removes all columns from interstitial levels, enabling open areas for performance and art installations that complement the neighbourhood’s reading culture. Intimate stalls encourage careful browsing and slow conversations, and as visitors filter down from upper floors, small restaurants and shops populate converted office spaces. Through a gradual transformation of the neighbourhood starting from the top down, this project offers a vision of Jimbocho that respects its historical bookseller storefronts while providing a playscape found nowhere else in the city.