The theory of comparative advantage is at the core of neoclassical trade theory. Yet we know little about its implications for how nations should conduct their trade policy. For example, should import sectors with weaker comparative advantage be protected more? Conversely, should export sectors...

The theory of international trade has paid scant attention to market institutions. Neither neoclassical theory nor new trade models typically specify the process by which supply and demand meet. Yet in the real world, intermediaries play a central role in materializing the gains from exchange...

This paper develops a simple model of international trade with intermediation. We consider an economy with two islands and two types of agents, farmers and traders. Farmers can produce two goods, but in order to sell these goods in centralized (Walrasian) markets, they need to be matched with a...

When asked to name one proposition in the social sciences that is both true and non-trivial, Paul Samuelson famously replied: `Ricardo's theory of comparative advantage'. Truth, however, in Samuelson's reply refers to the fact that Ricardo's theory of comparative advantage is mathematically...

We review a recent body of theoretical work that aims to put numbers on the consequences of globalization. A unifying theme of our survey is methodological. We rely on gravity models and demonstrate how they can be used for counterfactual analysis. We highlight how various economic...