To a large extent, the recent interest in the geographic distribution of economic activity marks a return to earlier times. Both of the two primary disciplines – economics and sociology – that inform the study of strategy began with explicit consideration of the importance of geography. On...

Studies consistently find regions dense in concentrations of similar firms to be fecund sources of new firms of the same kind. This pattern persists even in industries with negative returns to geographic concentration. Why do these patterns persist? On the one hand, social networks may constrain...