In the moment of global change, the “monitoring of change” is identified as one of the key challenges. The analysis of the territorial transformations increasingly rely upon integrated services based on geospatial information, creating thus a progressive demand of data sets and service providers and aiming at an extensive availability of these information. Such request, gradually distinguished in time-scale or frequency, resolution or territorial extension, requires shifting from Web Map Services (WMS) towards Web Processing Services (WPS) in order to fully interact with the end-user. To this purpose, technological progress and aspect of territorial dimension should be considered, especially when dealing with built environment. In order to integrate geospatial data into decision making processes, remote sensing data need to be integrated by in-situ data collection so as to support the local scale of intervention. The two examples of open source geo-portal here illustrated are: Atl@nte (Atlas of historical cadasters and topographic maps of Lombardy) and Geocluster mapping tool (Project GE2O, FP7). The first example shows how geo-referenced historic maps at territorial (regional) and cadastral (local) scale can be integrated with remote sensing data sources to address regional and local interventions, while the second example provides an illustration of mapping and geo-clustering of the phenomena relevant to energy efficiency in buildings. The paper investigates the potentials of geo-portals as planning instruments developed to share multi-temporal/multi-scale spatial data, responding to end-users’ demands and in relation with specific INSPIRE themes, to provide exhaustive monitoring and ensure informed decision making.