Leo Hollis is a writer and historian who lives in London and has been a longtime defender of urban life. In this wide-ranging and buoyant work, he charts the advantages of life in the city in the face of "the grumbles of the skeptical and the stuck-in-the-mud naysayers" who continue to condemn it as a drain of our humanity and a source of filth, noise, violence, and pollution.

In his examination of what a city is, Hollis shares his delight in walking the streets of London; compares Barcelona in Spain with Houston, Texas; ponders the first cities; salutes Jane Jacobs and her linking of city and complexity; and challenges us to think about new ways of living together that benefit us all.

In the city, we are free to pursue our own interests and this makes it a very exciting place. But the conflict and competition to get ahead and succeed also makes it a place of incredible inequality where the rich and powerful dominate and run the city from above. While Hollis is saddened by this fact, he still clings to the notion that there is a spirit to cities that can be found in its parks and public places where citizens meet. He agrees with William H. Whyte who says of city dwellers: "What attracts people most is other people. Many urban spaces are being designed as though the opposite were true."

In 2007, 50% of the global population became urban and this number is expected to rise to 70% by 2050. Hollis believes that redefining what community means in these urban centers is more important than ever. The density of city life forces people to adapt their behavior — to be more open to diversity and more civil as they mingle with strangers. Being a good neighbor comes alive in conviviality — "a tradeable commodity that creates a better place around us."

Perhaps the biggest challenge is eradicating urban slums around the world and providing a better life for their residents. Hollis takes a look at efforts being made to help refugees and others who are fleeing from rural areas. He also covers new experiments with smart cities — built according to the new rules of the Information Age. Another challenge facing urban dwellers is lack of parking spaces in cities: urban designers and others are working on reducing automobile traffic and adding parks, sports courts, and gardens. Last but not least, Hollis celebrates the greening of cities.