The second half of the twentieth century saw large-scale suburbanization in the United States, with the median share of residents who work in the same county where they live falling from 87 to 71 percent between 1970 and 2000. We introduce a new methodology for discriminating between the three...

We present a theory of spatial development. A continuum of locations in a geographic area choose each period how much to innovate (if at all) in manufacturing and services. Locations can trade subject to transport costs and technology diffuses spatially across locations. The result is an...