PTAs are generally negotiated without any tariff concessions or transfers to non-member countries. Can such a PTA benefit the neighbors' welfare? In a two-good competitive equilibrium model in the absence of an entrepôt, a PTA without concessions to the outside will hurt the outsider's welfare...

We develop a model of international trade with increasing returns to scale by taking into account the possibility of cooperation among agents in an egalitarian economy. It is shown that each country gains from trade in a trading world in which there are arbitrary numbers of...