This document has been prepared by Marc Murtra and Francesc Trillas. A large number of expert personalities have also made contributions, from an initial draft. None of these personalities is responsible for the final document. But they have all helped to enrich the document. The initial draft was the subject of a public debate between Marc Murtra, Alicia Romero and Emliliano López-Atxurra, moderated by Francesc Trillas.