We model an international union as a group of countries deciding together the provision of certain public goods and policies because of spillovers. The countries are heterogeneous either in preferences and/or in economic fundamentals. The trade-off between the benefits of coordination and the...

We model an international union as a group of countries deciding together on the provision of public goods or policies that generate spillovers across members. The trade-off between benefits of coordination and loss of independent policy-making endogenously determines size, composition and scope...