In the face of networked societies and economies that defy national borders, some argue that cities are superseding nations in their ability to address our most pressing challenges: the need for environmental sustainability, the provision of key resources and services, and the maintenance of effective governance. We heard from Dr. Benjamin Barber, political theorist and author of If Mayors Ruled the World: Dysfunctional Nations, Rising Cities; Vishaan Chakrabarti, architect, planner, and author of A Country of Cities: A Manifesto for an Urban America; and Alexandros Washburn, Urban Design Chief of New York City and author of The Nature of Urban Design: A New York Perspective of Resilience in a conversation exploring the political, economic, and cultural potential of cities as sites of problem-solving and innovation. The discussion was moderated by Saskia Sassen, the Robert S. Lynd Professor of Sociology at Columbia University and author of books including Territory, Authority, Rights: From Medieval to Global Assemblages.