摘要:Highlights Urban areas are highly complex systems, with interconnections between their political, economic, social, natural and built environments components, and each with its own unique priorities and contexts. They are also facing key global and local sustainability challenges such as a changing climate, air pollution and waste, all of which also present risks for population health. Improving urban sustainability can provide co-benefits for population health; however, the effectiveness—or unintended consequences—of policies or actions can depend on the behaviours and relationships in the wider urban system. The papers published in this special issue explore issues related to urban sustainability and health, including urban design and environmental justice, scale, and informal settlements. The papers also describe issues at the interface of different system components, demonstrating the systemic challenges that can act to enhance or prevent sustainable change. The complexity of urban environments presents challenges for research and policy, both of which can be reductive, and conducted independent from other disciplines or government departments. However, by moving from this siloed approach towards a broader systemic understanding, there are opportunities to develop and implement evidence-based solutions that have the potential to lead to significant improvements in sustainability and health.