Ellen's work has centered on what happens when aging infrastructure, from shopping malls to office parks, no longer serves the communities around them. As co-author of Retrofitting Suburbia, she helped define a movement and a moment. The book documented how underperforming, car-dominated spaces could be reimagined into walkable, resilient, and socially connected environments. Over time, her research expanded into a growing database of more than 2,500 retrofit projects. These case studies explored how design can address public health, climate resilience, economic development, and equity, all through the lens of reuse rather than expansion. Her work, now seen as central to strategies for the sustainable reinvention of our cities, has made her one of the most influential international urbanists