Cities can be thought of as the absence of physical space between people and firms. As such, they exist to eliminate transportation costs for goods, people and ideas and transportation technologies dictate urban form. In the 21st century, the dominant form of city living is based on the...

Many metropolitan areas have experienced extreme boom-bust cycles over the past century. Some places, like Detroit, grew enormously as industrial powerhouses and then declined, while other older cities, like Boston, seem quite resilient. Education does a reasonable job of explaining urban...

220 million Americans crowd together in the 3% of the country that is urban. 35 million people live in the vast metropolis of Tokyo, the most productive urban area in the world. The central city of Mumbai alone has 12 million people, and Shanghai almost as many. We choose to live cheek by jowl,...

Empirical research on cities starts with a spatial equilibrium condition: workers and firms are assumed to be indifferent across space. This condition implies that research on cities is different from research on countries, and that work on places within countries needs to consider population,...

Employment growth is strongly predicted by smaller average establishment size, both across cities and across industries within cities, but there is little consensus on why this relationship exists. Traditional economic explanations emphasize factors that reduce entry costs or raise...

Carbon dioxide emissions may create significant social harm because of global warming, yet American urban development tends to be in low density areas with very hot summers. In this paper, we attempt to quantify the carbon dioxide emissions associated with new construction in different locations...