In the short run, EMU means substantial costs - one only has to think of all the activities related to the changeover weekend at the start of this year and the forthcoming replacement of banknotes and coins.
At the macro level, there were also the unpleasant short-term effects of disinflation and fiscal consolidation required in many member states to qualify for participation in the monetary union. Note, however, that these measures would in any case have been necessary, with or without EMU.