Geohazard mapping has been developed using multi-form, digital image data, permitting a regional assessment of risk concerning slope instability. Landsat Thematic Mapper and multi-temporal SPOT-Panchromatic image data have been processed to identify land use patterns and soil mineralogy information, supported by field measurements using spectroscopy and X-Ray Diffraction (XRD). These have been used to identify slope instabilities generated by the storm that struck Piemonte in November 1994. This event caused many fatalities and produced widespread mass movement, flooding and consequential damage to property. Slope angle and slope aspect data were derived from a Digital Elevation Model (DEM), produced from stereo air-photographs. The geohazard map was then compiled by merging digital slope data with geotechnical characteristics,utilizing map algebra within a Geographical Information Systems (GIS).