The history of monetary unions is a relatively unexplored area in economics. Yet it should be able to provide guidance for Europe's venture into monetary union. In Readings 50, Michael Bordo and Lars Jonung discuss both the history and the lessons it may hold for EMU. Their paper is followed by six commentaries by other distinguished economists with a variety of viewpoints on monetary union. The book is introduced by Robert Mundell who pioneered the optimal currency area approach and who was awarded the Nobel Prize in economics in 1999.