[en] The future of nuclear energy may require breeding and optimized waste management. Innovative technologies have to be explored, in order to reduce considerably the ore consumption and the associated waste production. Sodium-cooled fast reactors seem to be the most achievable technology in the coming decades, and can play an important role to launch the generation 4 technologies. However, the standard sodium-cooled reactors face to the problem of the positive void coefficient and a major Minor Actinides (MA) production if transmutation is not considered. In this context, we perform neutronics studies on innovative (or evolutive) sodium-cooled reactors. These studies are based on MURE (MCNP Utilities for Reactors Evolution), a C++ object-oriented evolution code that couple the Monte-Carlo transport code MCNP with a fuel depletion code under given conditions (constant power, refueling, reactivity adjustment,..). By construction, MURE is very versatile and offers the possibility to interact with the system during the evolution. Different ways of evolution such as predictor-corrector methods, hybrid multi-group binning approach are used to speed up MCNP run time (at least a factor 30), - In a first part, a 'reference' case, a SFR without recycling MA, is presented; a propagation of statistical error is shown during the whole evolution and several methods are compared (predictor-corrector, hybrid multi-group binning,..). Different configurations of a fast sodium cooled reactor (SFR, ∼1 GWe) are investigated, as for example a U/Pu core MA-loaded Uranium blankets have been studied and compared to a 'reference' standard U/Pu systems. The evolution is performed until equilibrium. Safety parameters during the whole evolution are studied, particularly void coefficient degradation because of presence of minor actinides. The radiotoxicity of the waste leaving the reactor has been calculated and compared to the 'reference' case. We also consider the use of thorium fuels, using U or Pu as fissile material. A self-breeding Th/U configuration has been found, using thorium blankets and is characterized by a negative void coefficient. Comparison of produced wastes in different strategies (transmutation of MA or not) will be presented. (authors)