Hysteresis, the Phillips curve and the costs of monetary union

If actual unemployment affects the non-accelerating inflation rate of unemployment (NAIRU) through a hysteresis effect, the disinflation involved in reducing a country's inflation rate to that of its future partners in a monetary union could produce a long term cost to monetary union in the form of a lasting rise in the NAIRU. This note sets out a framework for analysing the likelihood of such an eventuality.