How do we guarantee energy independence and secure supplies, while improving safety standards, optimising our management of materials, and minimising waste production? And all this without emitting greenhouse gases? These are the specifications for future nuclear systems defined by the Generation IV International Forum (GIF). Within the scope of the French Act dated 28 June 2006 on the sustainable management of radioactive materials and waste, the CEA has proposed a fourth-generation integrated technology demonstrator project called ASTRID, which is currently in its conceptual design phase.