The study is part of a wider multidisciplinary research project within the UNESCO-Man and Biosphere (MAB) Programme on the city of Rome. The aim of this part of the study is to investigate the perception the inhabitants have of the quality of their residential environment, in order to find out (i) the principal evalutative dimensions underlying these perceptions and (ii) how these evaluations are affected by the temporal dimensions of the residential experience: i.e. the length of residence and the amount of daily time spent within the quarter of residence. A sample of about 500 subjects all from the same quarter of the city, was considered.