The project aims to undertake an historical, archaeological and art historical study of the monasteries in medieval Rome. This is a topic so far not covered, both because of the heavy restoration of the structures where the regular life took place, as well as the dispersion of the archival funds that has made it difficult reconstructing the historical events of many sites. Therefore, this research intends to take advantage of a synergy of historians, archaeologists and art historians who, through the analysis of some case studies, may begin to shed new light on a surprisingly unknown subject. The key point of the project will be the study of historical, graphic and iconographic sources through targeted investigation of some archival funds related to the history of the sites (i.e. Archivio Segreto Vaticano, Archivio di Stato...) and to the restorations (i.e. Archivio Centrale dello Stato, ICCD...), as well as the systematic examination of edited sources and the comparative analysis of masonries, plans and architectural typologies in order to: 1) review the history of complexes still unknown; 2) trace the architectural phases of the monasteries; 3) investigate the role and the different settlements of the various orders in the city; 4) reconstruct the diachronic evolution of the monastic phenomenon in Rome, from high to low Middle Ages; 5) investigate the relationships between mother-houses and their dependencies. Among the most relevant sites, both for history and monumental structures, will be analyzed: S. Lorenzo fuori le mura, S. Saba, Ss. Quattro Coronati, S. Paolo fuori le mura, S. Lucia in Selci and S. Agnese fuori le mura (Benedictines), S. Maria in Cosmedin (Greek monks), S. Cosimato (Benedictines-Poor Clares), Tre Fontane, S. Pancrazio and S. Sebastiano (Cistercians), S. Croce in Gerusalemme (Carthusians), S. Lorenzo in Panisperna, S. Silvestro in Capite (Poor Clares), S. Sisto vecchio, S. Maria sopra Minerva and S. Sabina (Dominicans).