Green, sustainable, compact, frugal, resilient, and intelligent cities… In all the world’s big cities, environmental urgency has led to the proliferation of urban projects to reduce pollution, waste, and environmental footprints. Different models of optimal natural resource management have emerged to recast urban land and service management (water, waste, energy). The terms of the debate often boil down to a choice between the pursuit of massive investment programs in big technical systems and the implementation of decentralized, miniaturized, and even individualized solutions for buildings, city blocks, and neighborhoods. However, between “business as usual” and decline, a third path is apparent: frugality.