We examine the impact of Urban Mobility Plans (UMP), imposed by the LAuRE law of December 30, 1996, on spatial accessibility to principal destinations, such as hospitals or schools. We use the open-source Geographical Information Sys-tem OrbisGIS, paired with its Open Geospatial Consortium complaint spatial database H2 and its extensions H2GIS and H2Network, to produce accessibility indicators. We cross these indicators with demographical data to produce service area maps and nu-merical statistics. These indicators may be used to evaluate the effectiveness of UMPs.