The research presented in this paper introduces a user context approach for the implementation of an adaptive Geographical Information System (GIS). The main focus of the paper is on presenting some implementation issues about the data used and their evaluation with respect to their suitability for the user interacting with the system. For the evaluation of the geographical information, the system uses a simple decision making model and selects the one that seems more appropriate for a user. In this way, the GIS has the ability of adapting its interaction to each user and make interaction more user friendly.