An important part of the risk management of natural hazards in mountain regions concerns the hazard assessment and the planning of protection measures in steep headwater catchments, i.e. torrent control and slope stabilization. Torrent processes in steep channels have their rightful place among the various alpine natural hazards and the corresponding control measures have a long tradition in the European alpine countries. In the planning and execution of such measures, professional experience has been of paramount importance. This experience was based primarily on observations made during...