Since the first human settlements, people have understood that proximity to nature and open space is fundamental to every aspect of quality of life. But cities are not organized to optimally develop open space, because the landscape of a city falls under many ownerships, both public and private. With Mott Haven in the South Bronx as its laboratory, the Haven Project aims to demonstrate—through a revolutionary combination of capital renovation and data collection—that optimizing the built environment will measurably increase local health, safety, economic activity, and joy.