European Union, European Integration, Turkey, European Council, Theories of Integration
- Since 2016 Director of the Centre for Turkey and European Union Studies CETEUS) at the University of Cologne
- 2016 Vision for Europe Award of the Prague European Summit
- 2015 Awarded with “Universitätspreis Forschung“ by the University of Cologne for his excellence in research
- Since 2013 Academic leader of the master degree programm „European and International Affairs“ of the Turkish-German University, Istanbul
- 2011 Awarded for ‚Lifetime Achievement in Contemporary European Studies‘, University Association for Contemporary European Studies (UACES)
- Since 2011 Holder of an ‚Ad Personam‘ Jean Monnet Chair
- Since 2010 Vice-President of the German consortium for the foundation of the Turkish-German University, Istanbul
- 2009 - 2010 Lecturer-in-residence of the Centre of European Union Studies at the University of Salzburg
- 2007 Jean Monnet Award „European Prize for Lifelong Learning/European Studies“ in Gold
- 2004 - 2005 Titulaire Chaire Alfred Grosser, Sciences Po.
- 2000 Jean Monnet Chair Fellow at Robert Schuman Center for Advanced Studies, European University Institute, Florence.
- 1999 Chaire Européenne at Sciences Po, Paris.
- Since 1998 Coordinator and co-coordinator of several European wide, regional and local Jean Monnet Networks and Centres of Excellence.
- Since 1997 Visiting Professor at the Diplomatic Academy of Vienna, Europainstitut Basel, Institute for Advanced Studies Vienna, Centre International de Formation Européenne (CIFE), Berlin/Nice.
- Since 1996 Visiting Professor at the College of Europe, Bruges and Natolin/Warsaw.
- 1995 - 2016 Chairperson of the Trans European Policy Studies Association (TEPSA), Brussels.
- Since 1995 Chairperson of the Institut für Europäische Politik (IEP), Berlin/before 2000: Bonn.
- 1994 - 2016 Holder of the Jean Monnet Chair for Political Science, University of Cologne
- 1990 Venia legendi in Political Science of the University of Bonn.
- 1980 - 1996 Director of the Department of Administrative and Political Studies at the College of Europe, Bruges.
- 1979 Doctorate in political science at the University of Cologne.
- 1973 - 1993 Director of the Institut für Europäische Politik, Bonn.
- Jahrbuch der Europäischen Integration, Bonn/ Baden-Baden 1981-2016ff (Ed. with Werner Weidenfeld).
- Europa von A - Z. Taschenbuch der Europäischen Integration, Bonn/Berlin/Baden-Baden 1991-2016ff. (14th Ed) (Ed. with Werner Weidenfeld; various translations).
- The European Council, Basingstoke 2016.
- Das politische System der Europäischen Union, Wiesbaden 2008.
- The Constitutional Treaty: Three Readings from a Fusion Perspective, in: Journal of Common Market Studies, Annual Review 2004/2005, p. 11-36.
- An Ever Closer Fusion? A Dynamic Macropolitical View on Integration Processes, in: Journal of Common Market Studies, Vol. 35, No. 2 (1997), pp. 267-299.