Beyond aesthetics, Design impacts everyone and enables us to enjoy: Improved wellbeing in mind and body, business & medical outcomes; reductions in loneliness, isolation and crime; safe neighborhoods and strong communities. Or, it can interfere with all of these. Data collected in & on spaces reveals correlations between spatial design and human behavior. Just as roadway designs are optimized through simulated traffic, Designers could iteratively simulate the design of built environments and study the resulting behaviors. Can designers tune design for desired human behavior? Who decides?