This paper focuses on the potentialities offered by mobile phone data to a reading of the site practices and rhythms of usage of the contemporary city by identifying the principal mobile practices of different urban populations. Beginning with the results of a research carried out in the Italian region of Lombardy, utilising mobile phone data provided by Telecom Italia, the paper will demonstrate how new maps, based on mobile phone data and better tailored to the dynamic processes taking place, can represent spatialized urban practices, provide new insights into the analysis of space-time patterns of mobility practices and be employed to recognise different “communities of practice” (WENGER, 1998). Mobile traffic data were treated as the ef...