We should emphasize that from the second half of the 1990s, when in Siena as in the rest Italy we began to use Geographic Information System for the management and analysis of archaeological data, we have felt a progressive schism between work in the laboratory and work in the field. While the availability of advanced technologies has been rapidly growing, activities in the field have continued to make use of instruments and methodologies developed in the 1970s. The problems arising from this situation are mainly inherent in the collection of data that lack the accuracy required by GIS, or which rely work to a different kind of rational logic and the unavailability in the field of the large amount of data stored in the desktop GIS.