This fully revised second edition reflects the great expansion in urban ecology research, action, and teaching since 2015. Urban ecology provides an understanding of urban ecosystems and uses nature-based techniques to enhance habitats and alleviate poor environmental conditions. Already the home to the majority of the world's people, urban areas continue to grow, causing ecological changes throughout the world. To help students of all professions caring for urban areas and the people, animals, and plants that live in them, the authors set out the environmental and ecological science of cities, linkages between urban nature and human health, urban food production in cities, and how we can value urban nature. The authors explore our responsibilities for urban nature and greening, ecological management techniques, and the use of nature-based solutions to achieve a better, more sustainable urban future and ensure that cities can climate change and become more beautiful and more sustainable places in which to live. This text provides the student and the practitioner with a critical scientific overview of urban ecology that will be a key source of data and ideas for studies and for sound urban management.