Should a subset of member states of a federation be allowed to form a sub-union on some policy issue? When centralization is not politically feasible, allowing an enhanced cooperation agreement among a subset of countries permits the latter to gain benefits which would otherwise be lost....

Since Jean Monnet conceived the Coal and Steel Community, free trade has successfully prevented serious conflicts in Europe between democratically governed States with market economies. After six countries established the European Community, this principle has been extended successfully to its...

We develop a two-country, two-sector model with a continuum of workers to address the link between migration and trade where policy is determined by a simple referendum. In particular, we address two questions. First, are states already in free trade areas more likely to support full integration...