This study used the case of summer 2018 in London to show that rooftop photovoltaics could have reduced heat-related mortality by 12% while cool roofs could have reduced it by 32%. In addition, rooftop photovoltaics generate up to 20 TWh of electricity.

How widespread is the possibility of creating ‘15-minute cities’? Using openly available data, the authors measure access to essential services and what points of interest would have to be relocated to create 15-minute cities. With novel quantification, they demonstrate remarkable differences among cities across different regions of the globe.

This study proposes that the optimal allocation of roof area for rooftop agriculture and photovoltaics is 61% of the flat rooftop area to the former and the rest for the latter. However, maintaining this productivity requires considerable water use and materials.

City governments are moving to integrate justice and equity concerns into climate action. Diezmartínez et al. demonstrate that contestations about the politics of climate justice were central during the first 2 years of implementation for a Boston building decarbonization policy, highlighting important challenges in translating climate justice into practice. Nature Cities is proud that this robust work is our first fully qualitative methods study.

The iconic image of ‘the public square’ typifies many cities in Europe and elsewhere, but they transcend spaces for socializing and public deliberation. Focusing on Munich, this study analyzes whether and how design features of public urban squares affect the broader biodiversity living there, finding that greenness matters but that different taxa respond differently to design elements.

This Article calculates how three barriers (water, steep mountains and national borders) limit urban growth and interconnectivity for more than 13,000 cities around the world. It found that natural barriers are associated with denser, smaller, greener and less land-hungry cities.

Water is life. Water is beautiful. Water is dangerous. Water researcher Marie Garcia reflects on how building meaningful relationships with Detroiters helps to shape her relationship with the city, especially as its longest-term residents struggle with worsening flood impacts on their homes and lives.

In this issue of Nature Cities, we highlight the policy relevance of urban research to a variety of domains. These applications also foreground the importance of city policy for mediating connections between human society and the natural environment.

Urban archaeology in the humid tropics advances a new and diversified ontology of urban spatial forms, functions and processes that enriches and expands the frame of reference for what cities were in the past, what they are in the present and what they can be in the future.

Interdisciplinary dialogue is crucial in framing new perspectives on urban life and in developing analytical frameworks suited to the complex realities of urban contexts.