Urban ecosystems are key to protecting biodiversity in cities and other urban areas. Cities can play an important role in hosting rare and endangered species and habitat types. Biodiversity provides a number of important ecosystem services to urban residents, including providing recreational space, filtering air particles, cleaning water and buffering climate extremes, such as heatwaves. Nature and biodiversity, and the ecosystem services they provide, can have a positive impact on the quality and sustainability of life in cities, once they are properly managed and maintained.