This volume contains the proceedings of the conference held in Cortona, October 6-9, 2004, that was organized as part of the project "Theoretical Physics of Nuclei and Many-Body Systems" involving 17 Italian Universities and sponsored by the Italian Ministery of Research and University. All invited papers on the main subjects of the project as well as all the individual contributions on special topics are included. As such these proceedings review the work performed in the last two years by the participating Italian community of nuclear theorists. In addition, in a panel international...