The aim of this study is to develop new methods for landslides mapping and water resources protection and management using geotypes and GIS. The first part of this report deals with the conception and the use of a new methodology for groundwaters’ protection areas delimitation. This study was carried out as part of an assignement for Canton de Vaud ; the results obtained for the Morges pilot area are already applied. The second part introduces the bedrock of a new method for landslide susceptibility mapping ; it involves the designation of mains hydrogeological factors for unstability predisposition, in situ method of estimation of these factors and, to finish with, the development of a sketch methodology and its implementation to eight sites.