The Journal of European Integration has, since 2006, its home in Maastricht, with Executive Editors based at Maastricht University and at the European Institute of Public Administration. Maastricht is a city with many European credentials, but - for the better or worse - none is better known globally than the EU treaty that carries its name, and which was signed here in February 1992. Given the journal's close association with the city, and hence with the prominence of the Maastricht Treaty, we took the twentieth anniversary of its signing as an occasion to devote a special issue of the journal to the reflection on the continuing significance of that historic event - a decision further reinforced by the stimulating debates we had about that topic in the context of an international conference organised in the city on the date of the anniversary.