[en] The framework of present ENEA (Italian Agency for Energy New Technologies and the Environment) research on fission reactors is briefly illustrated. The present situation and perspective leaves room for the exploration of new reactor designs which need to come to maturity to be proposed for future applications. The ENEA program gives priority to the design of innovative reactors which are possibly closer to realization (AP 600 and SBWR) and to the development and testing of innovative safety systems and components. Studies are extended to longer range design developments such MARS, PIUS and PRISM, to the fuel cycle and long-lived radioactive wastes and to the safety improvement of Central Europe and CIS nuclear plants