Since 1997, scientific congresses have been held every two years, usually under sponsorship of one of the national societies. Since 2007 scientific congresses are holding annually.
1997 - Maastricht, Netherlands
1999 - Florence, Italy
2003 - Berlin, Germany
2005 - Paris, France
2007 - Lisbon, Portugal
2008 - Rome, Italy
2009 - Istanbul, Turkey
2011 - Athens, Greece
2012 - Madrid, Spain
2013 - Prague, Czech Republic
2014 - Geneva, Switzerland