Co-organizer with M. Ballevre of the 9th Alpine Workshop (Cogne, Italy, 2009)
Co-convenor with M. Strecker of international meeting on “Shaping the Earth's Surface -Dynamics and Changing Environments" sponsored by the Geologische Vereinigung and German Science Foundation, DFG, (Univ. of Potsdam, 2006)
Speaker, Cluster of Excellence Initiative on “Coupled Earth Processes” (Berlin-Potsdam, 2006)
Convenor of the Dahlem Workshop on “The Dynamics of Fault Zones” (Berlin, 2005)
Scientific Advisor to Meetings on “Deformation Mechanisms, Rheology, Tectonics” (St. Malo 2003, Zürich 2005)
Co-convenor with G. Dresen of international conference on “Deformation Mechanisms, Rheology, Tectonics” (Neustadt-an-der-Weinstrasse, 1999)
Convenor of international short courses on “Fabric and Rheology of Geological Materials” at the Univ. of Giessen (1995, 1996, 1998) and Univ. of Vienna (2003)
Referee for the German Science Foundation, DFG (1999-2004)
Guest referee for the Swiss National Science Foundation (SNF), Natural & Environmental Research Council (NERC, United Kingdom), National Science Foundation (NSF, U.S.A.), Research Council of the ETH-Zürich (Switzerland), Czeck Research Council
External referee/member, faculty appointment committees for Univ. of Graz (Austria), Dalhousie Univ., New Brunswick, Univ. of British Columbia (Canada), Univ. of Bonn, Univ. of Greifswald (Germany)
Guest examiner for PhD theses at the Univ. de Paris IV (France), Univ. of Utrecht (the Netherlands), ETH-Zürich, Univ. of Lausanne, Univ. of Basel (Switzerland)
Reviewer for Earth & Planetary Science Letters, Eclogae geologicae Helvetiae (Swiss Journal of Geosciences), Geological Society of London, Geology, GSA-Bulletin, Geophysical Journal International, International Journal of Earth Science, Journal of Geodynamics, Journal of Geophysical Research, Journal of Petrology, Journal of Structural Geology, SMPM, Tectonics, Tectonophysics (editorial board 1998-2001), Terra, Quarternary International
Book reviews for Springer Verlag, Princeton Univ. Press