Landslides are one of the most serious natural and man induced hazards. The paper presents an innovative system dedicated to the measurement of landslide warning index. The system is based on a geographic information system (GIS) inference engine which properly combine satellite Earth observation (EO) measurements and static geophysical parameters. The system has been developed in the framework of an FP5 European project and it is aimed to provide an operative and flexible tool for public and private entities involved in land management, and in particular in mitigation of both landslide hazard and risk. Particular attention will be devoted to the role that the GIS environment plays as optimal measurement environment since it provides flexible interface between human (both high level geophysical experts and low level end users) and data (heterogeneous data in input to the geophysical model, warning maps in output).