The development of complex spatial-referencing (geomatic) tools gives rise in archaeology to information systems which result from the specific products of spatial information, data structures, thematic analyses, and particular scales and methods of analysis. In effect, the systems of GIS allow processing of the archaeological information, organised on the basis of the nature of the spatial data, at several scales (an excavation, town, micro-region, region etc.). The functions available to these tools allow new methods of data exploitation and give birth to multiple thematic maps. The acquisition of the spatial data is facilitated by the linkage of GIS to specific geo-referencing tools (e.g. GPS), or to topography. GIS allows the management and manipulation of information from various origins (satellite images, aerial photographs, thematic maps or environmental data-bases and antique maps etc.) and allows the archaeological data to be presented in its wider spatial context. Moreover, they also provide access to spatial analysis tools developed by geographers, permitting the cross-analysis of quantitative and qualitative data and resulting in specific applications to archaeological remains: analysis of the provenance of materials, predictive models, and analyses of distance and context. The construction of systems for the spatial referencing of information specific to archaeology, in different institutions, according to operational or scientific objectives, gives rise to the issue of how best to exploit the capacities of GIS for the management of data, and their potential as research tools. In this light, the difficulties of implementation concerning, in particular, organisation of data/data structure and use of spatial analysis tools have created specific methodological needs. In order to address these problems and needs, the creation of the ISA (Information Spatiale et Archéologie) network is proposed to bring together all the developers/researchers and users of spatial information systems in archaeology.