[영문]The economic case for European monetary union was shaky at best when it was first discussed 35 years ago. Europe's leaders felt that monetary union was the capstone to their efforts to create an integrated Europe, and much to the rest of the world's surprise, they succeeded. The introduction of the euro and the establishment of the European Central Bank (ECB) as the monetary authority of Europe went much more smoothly than many predicted. But nagging doubts about the wisdom of integration persist. The slim margins by which the Maastricht Treaty passed and the wide margin on which the European Constitution failed are reminders that Europeans are still wary of giving up their national sovereignty. This wariness also influences the ability of the ECB to efficiently take over monetary policy and limits the ability of the euro to become a true rival of the dollar in global financial markets.