World Cities Day, the culmination of a month of activities, events and discussions on urban sustainability known as Urban October, aims to promote international interest and cooperation around issues of urbanisation and the opportunities and challenges it presents, so contributing to sustainable urban development around the world. The day complements
Sustainable Development Goal 11, to make cities 'inclusive, safe, resilient and sustainable.'
The theme for 2021 is Adapting Cities for Climate Resilience. Cities worldwide are increasingly suffering the effects of climate-related disasters, such as floods, droughts, sea level rise, heatwaves, landslides and storms. Creating more sustainable, climate-resilient societies involves addressing a range of issues including poverty reduction, ensuring basic services livelihoods, the provision of accessible, affordable and adequate housing, investing in infrastructure, upgrading informal settlements and managing ecosystems. Successful, well-governed cities will greatly reduce climate-related risks for their populations.