Global challenges such as climate change, resource scarcity and poverty must increasingly be tackled in cities. While cities can be significant contributors to climate change and resource scarcity, and face considerable risks as a consequence of these, they are also central to the solutions for these challenges. The quality of infrastructure, reliability of service provision and other economic and political conditions in urban areas shape levels of resource use by, and exposure to risks for, residents. This paperwhich introduces a special issue on resilience and resource efficiency at the city scaleintroduces these two concepts and explores the nexus between them. It uses several case studies from different contexts to illustrate the relationship between these ideas, and describes how the papers in the issue engage with them.