Monetary Union with Voluntary Participation<xref ref-type="fn" rid="FN1">-super-1</xref>

A monetary union is modelled as a technology that makes a surprise policy deviation impossible and requires voluntarily participating countries to follow the same monetary policy. Within a fully dynamic context, we show that such an arrangement may dominate a regime with independent national currencies. Two new results are delivered by the voluntary participation assumption. First, the optimal plan is shown to respond to a country's temptation to leave the union by tilting both current and future policy in its favour. This yields a non-linear rule according to which each country weight in policy decisions is time-varying and depends on its incentive to abandon the union. Second, we show that there might be conditions such that a break-up of the union, as has occurred in some historical episodes, is efficient. The paper thus provides a first formal analysis of the incentives behind the formation, sustainability, and disruption of a monetary union. Copyright 2006, Wiley-Blackwell.