Until recently Radiology Information Systems (RISs) were considered a set of separate, often heterogeneous applications at the functional, technological and architectural level. In last years, the need for an integrated methodological approach and an engineering vision of the system design has become the most important aspect in the implementation of RISs. Based on this approach, the fundamental organizational, operational and clinical objectives of an advanced RIS together with the major critical factors of success, are presented. Such objectives and requirements have constituted the starting basis for the implementation of the DREAM (Distributed radiological environment advanced and multimedia) system, the result of the collaboration of the "Università Cattolica del S. Cuore, Policlinico A. Gemelli" of Rome and "GESI-Gestione Sistemi per l'Informatica". An overview of the main functional characteristics, the most qualifying aspects of the system and the methodological approach followed in its implementation, are reported.