Following the disaster of Hurricane Katrina in New Orleans, people began to discuss and visualize the ways in which the urban structure of the city could be reorganized. Rather than defining the disaster recovery process as simply a matter of rebuilding the existing city, these voices called for a more radical rethinking of the city's physical, social and environmental systems. This idea of disaster as an opportunity for urban restructuring is a hallmark of a "design moment." Design moments are different from the incremental process of urban growth and development. Instead of gradual growth and change, design moments present the opportunity for a significant restructuring of urban form that can shape the city for decades to come. As such, a design moment presents a critical juncture in the historical growth and development of a city. In this book we explore the question: what does urban design have to do with a disaster like Hurricane Katrina? Focused on New Orleans, the authors explore different dimensions of the post-disaster design moment, including the politics of physical redevelopment, the city's history and identity, justice and the image of the city, demolition and housing development, and the environmental aspects of the recovery process. This book was published as a special issue of the Journal of Urban Design.