Introduction / Forrest H. Capie and Geoffrey E. Wood -- Theoretical issues pertaining to monetary unions / Bennet T. McCallum ; Comments by Peter Sinclair, Geoffrey E. Wood -- The future of EMU: what does the history of monetary unions tell us? / Michael D. Bordo and Lars Jonung ; Comments by Tim Congdon, Charles Goodhart -- How long did it take the United States to become an optimal currency area? / Hugh Rockoff ; Comments by Ronald McKinnon, Anna J. Schwartz -- The bank, the states, and the market: an Austro-Hungarian tale for Euroland, 1867-1914 / Marc Flandreau ; Comments by Luca Einaudi -- The future of the euro: a public choice perspective / Roland Vaubel ; Comments by Fabrizio Zampolli, Mark Salmon