A healthy society is about more than just preventing injuries and reducing the death toll from disease. It is also about having access to safe neighborhoods and affordable housing, broadening job opportunities and reducing income inequality, designing walkable towns and fostering community cohesion. It takes multiple interventions and cross-sector partnerships to do all of that, and data to determine what is working. Analytic tools and strategies from other disciplines offer some guidance for calculating impact, as does the distinctive perspectives of those who design, implement, and benefit from public health activities. How can we devise ways to measure advances in social well-being and health in its fullest sense? What indicators will help us understand what makes a healthy society?