ABSTRACT: The current approach for the seismic study of existing buildings is based on the individuation of the building's masonry category and on the choice of the appropriate mechanical parameters to perform reliable structural analysis. A collection and a review of a significant amount of available data obtained from the more used experimental test procedures, that are commonly exploited to determine the mechanical characteristics of masonry structures, were carried out in the framework of a research project financed by the National Civil Protection Agency. The purpose is to upgrade the procedures that define these tests, to interpret the results they provide and to update the variation ranges of mechanical parameters currently provided in the Italian Standards. Based on such considerations and on the analysis of the collected database, in the paper, some "operative" proposals regarding the procedure of tests' execution and the interpretation of the results they provide are shown.