Organizing
Chairs and Conference Organization
- Conference Chair of CADE 21 the 21st Conference on Automated Deduction
- Programme Co-Chair of KI 2006 the 29th Annual German Conference on Artificial Intelligence
- Programme and Conference Chair of MKM 2005 the Fourth International Conference on MATHEMATICAL KNOWLEDGE MANAGEMENT
- Programme Comittee Co-Chair of Workshop on Inference in Computational Semantics ICoS-3 Siena Italy (with Patrick Blackburn).
- Programme Comittee Co-Chair of the CALCULEMUS 2000 Symposion, St. Andrews Scotland (with Manfred Kerber)
- Programme Comittee Co-Chair of Workshop on Inference in Computational Semantics ICOS-2 Schloß Dagstuhl, Germany (with Johan Bos)
- Workshop Chair of The 17th International Conference on Automated Deduction CADE-17, Pittsburgh, Pa, USA
- Local-arrangements for the 18. German national conference on Artificial Intelligence (September 1994, Saarbr"ucken)
Other
- General Editor of the QPQ repository for deductive Software
- Member of the Executive Committee of the OpenMath Society
- Trustee of the Conference on Automated Deduction 2000-2006
- Trustee of the CALCULEMUS Interest Group 1999-2002, 2003-2006
- Member of the Math Working Group in the World Wide Web Consortium