Supervisor: Dr. Giovanni Michetti. Co-examiner: Dr. Gabriele Mazzitelli. This work aims to redefine the URBS (Roman Union of Specialized Libraries) website architecture, following three steps: analysis of the documentation about the creation of websites and library portals, with specific attention to interoperabilty (chapters 1 and 2); analysis of actual URBS website (chapter 3); new URBS website project (chapter 4). Starting from the discussions about OPACs and portals, and paying attention to the Minerva Project Manual and to the guidelines to accessibility and usability, the new URBS website should be developed into a fully functional integrated portal to give to its users a set of added value services.