I have organized, together with many collaborators and colleagues, quite a number of scientific conferences, workshops and other meetings. I have not kept track of all my activities in this respect. I was involved in the organization of three large scale international meetings to which I donated substantial amounts of time:

1. ICM'98 , TU Berlin, August 17-28, 1998
2. International Conference on Operations Research 1994, TU Berlin, August 30 -- September 2, 1994
3. Symposium on Mathematical Programming -- The State of the Art, Bonn 1982

I am currently a member of the organizing committee of the 21th International Symposium on Mathematical Programming,
Berlin, August 12-24, 2012.

My research group at ZIB organizes about half a dozen workshops per year, usually addressing our current research and application areas. The last international conference organized by this group was the CPAIOR 2011, May 23-27, 2011 at ZIB, Berlin.

In addition, I was involved in the local organization of the 25th IFIP TC7 Conference on System Modeling and Optimization (September 12-16, 2011, at TU Berlin).