We compare free trade reached through expanding regional trading blocks to free trade accomplished by multilateral negotiation. With sunk costs, the outcomes are different. Trade in an imperfectly competitive good flows disproportionately more between the original members of a regional agreement...

Big cities specialize in services rather than manufacturing. Big-city establishments in services are larger than the national average while those in manufacturing are smaller. This paper proposes an explanation of these and other facts. The theory is developed in an economic geography model that...