Why Tokyo's "15-minute neighborhood" experiment is being copied — and copied wrong — in seven cities

In the Setagaya ward of Tokyo, an urban planning experiment that began in 2019 has produced measurable results: residents report 23 percent fewer car trips, local retail revenue is up, and the ward’s carbon footprint from transport has fallen by roughly 12 percent. Seven cities across Europe, North America, and Southeast Asia are now attempting to replicate it. None of them are replicating the part that matters.

The 15-minute city concept — the idea that daily necessities should be accessible within a 15-minute walk or bike ride from home — has become one of urban planning’s most fashionable frameworks. Paris has adopted it as official policy. Melbourne has embedded it in its metropolitan strategy. But in most cases, the implementation has focused on the metrics while missing the mechanism.