There has been a broad discussion about the viability of the European Monetary Union (EMU) in its present and prospective confines. Generally, the EMU, consisting of 19 countries, is not considered an optimal currency area due to low labor market flexibility, autonomous fiscal policies, and structural differences among its members. Considerations about the endogeneity effect of currency unions lead to the question whether the EMU will become more viable over time. According to the endogenity hypothesis formulated by Frankel and Rose [1996, 2000], a common currency area may gradually become an optimal currency area at some future point (ex post unification), despite not having been an optimal currency area (OCA) prior to (ex ante) currency unification. Currency unification should bring about increased intra-industry trade and greater business cycle synchronization among member states. The most recent literature and analyses presented in this paper suggest that the endogenity effect in the EMU has been frail since its onset. While real convergence between EMU member states has not advanced, divergence in i.a. economic structures, national income and productivity levels is observed. The most important economic mechanisms reinforcing convergence and divergence among monetary union members are presented in this paper. Using recent data and related research results, we show a significant divergence in economic structures, business cycle synchronization and productivity levels among Eurozone members in the last decade. The Krugman sectorial dissimilarity index is applied to measure changes in industrial similarity among member countries and the Hodrick-Prescott filter to estimate business cycle synchronization in the EMU. These divergence tendencies have been strengthened by the global financial crisis of 2008 and persist, calling for reforms and new policies within the EMU.
