The IMF Working Papers series is designed to make IMF staff research available to a wide audience. Almost 300 Working Papers are released each year, covering a wide range of theoretical and analytical topics, including balance of payments, monetary and fiscal issues, global liquidity, and national and international economic developments.
This paper investigates whether a regional bloc would enlarge or remain stagnant in size using a model where enlargement is the endogenous outcome of the interaction between the supply of and demand for membership. We show that a maximum size of the bloc exists beyond which the regional policy-maker will be unwilling to enlarge further, and that either the supply side or the demand side of membership might be binding in the determination of the equilibrium size of the bloc. Furthermore, we analyze how the deepening of integration within a regional bloc affects its width. We show that deeper integration may lead to wider integration when the demand side of membership is binding in the determination of the equilibrium size of the bloc, while the equilibrium size of the bloc will be unaffected when the supply side of membership is binding.