The Italian Morality Atlas at municipality level, sponsored by the Health Ministry and realized by the Emilia-Romagna region in collaboration with the Institute of Medical Statistics of Milano, is aimed at: 1) supporting and stimulating the local production of mortality maps and the use of geographical data; 2) providing a working and research tool to local health planners; 3) setting a routine procedure for the detection of spatial clusters. This procedure is organized in several steps: the definition of the spatial domain and of the spatial distance metrics; the choice of the effect indicator and the standard population; the estimate of the density risk surface via kernel methods; the identification of "local maxima"; the analysis of local maxima for cluster detection; the description of the identified clusters. The paper investigates the meaning and the characteristics of spatial clusters, describes the procedure for their identification and discusses the opportunity to use an automated approach for map reading.