For African cities to grow economically as they have grown in size, they must create productive environments to attract investments, increase economic efficiency, and create livable environments that prevent urban costs from rising with increased population densification. What are the central...

The downsides of density, including traffic congestion, contagious disease and crime, were common in Victorian London and classical Rome, just as they are today in Sao Paulo and Lagos. Our urban past provides lessons for developing world cities today. The first lesson, that I highlight, is that...