Committees
1990-1993: European Committee for Future Accelerators, EFCA
2000-2009: Physics Working Group of SCAR (Scientific Committee on Antarctic Research)
2001-2008: External Review Committee of ANTARES
2003-2012: Peer Review Committee of ApPEC (Astroparticle Physics European Coordination)
2006-2012: Chair of the ApPEC Peer Review Committee
2003-2006: Chair of the R.W. Pohl Price Committee, DPG
2003-2006: External Review Committee APC (Paris)
2007-2013: Komitee für Astroteilchen-Physik, KAT
2011-2013: Chair of Komitee für Astroteilchen-Physik, KAT
2008-2011: PANAGIC (Particle And Nuclear Astrophysics and Gravitational International Committee)
since 2008: Editorial Board of the European Journal of Physics C
2009-2014: CERN Science Policy Committee
2011-2016: Kuratorium Physik Journal
2011-2012: KM3NeT Scientific Standing Committee
since 2011: NIKHEF Scientific Committee
since 2012: CTA Scientific and Technical Advisory Committee
since 2012: INFN International Evaluation Committeee
2013-2017: Stellv. Vorsitzender des Fachverbandes Teilchenphysik in der DPG
2013-2014: Scientific Committee of the Modane Underground Laboratory
since 2013: KM3NeT Scientific and Technical Advisory Committeesince 2013: Auger Scientific Advisory Committee
2014-2016: Astroparticle Physics International Committee (ApPIC)
since 2014: Science Advisory Committee of Baikal GVD
since 2014: Kuratorium Welt der Physiksince 2014: Chair GVD Technical Advisory Board