The results of multigroup calculations of continuous irradiation of Np, Am, and Cm in VVER-1000, PHWR-880, Superphoenix-1200, BREST-1000, and ELYaU-800 reactors are used to compare transmutation efficiency. The sources of continuous replenishment for the transmuters were Np, Am, and Cm extracted after a 3-yr holding period from the VVER and Superphoenix spent fuel. It is shown that the most effective transmuter is a subcritical liquid-fuel ELYaU system with an average thermal-neutron flux in the blanket 2·10 15 sec ‐1 ·cm ‐2 . For solid-fuel reactors, the continuous-irradiation model makes it possible to describe approximately the multiple transmutation regime. In the foreseeable future, one-time transmutation of Np, Am, and Cm in a solid-fuel reactor followed by storage in a long-term storage facility is feasible. The results of different computational variants for such regimes show that for transmutation in 10 yr in PHWR the radiotoxicity of Np, Am, and Cm accumulated in long-term storage reaches an equilibrium in no longer than 100 yr. Nuclear reactors used for transmutation actually become a kind of repository for sources of long-lived radionuclides. There is no need to prove that the content of the most dangerous (for humans) radionuclides in transmutation reactors today is incomparably more dangerous than storage in specially equipped enclosures at low temperatures and pressures. However, these considerations, in our opinion, should not be taken as a justification for considering research on transmutation as unpromising. The specialists who are proposing nuclear power as a large-scale and long-term method for producing energy are bound to develop and substantiate an effective method for eliminating harmful wastes produced as a result of such production. It is not ruled out that the practical application of transmutation will be needed only in the distant future, possibly in the period when nuclear power plants will not longer be operating. But, means must be expended even now on investigations which will make it possible to show the actual possibility of annihilating long-lived radionuclides. Otherwise, society may completely reject the use of atomic energy. In this paper, we present the results of investigations of the effectiveness of transmutation of long-lived radionuclides in reactor systems operating under closed fuel cycle conditions. The technological aspects of the problem, such as the arrangement of radionuclides in the reactor core, the influence of the radionuclides on the degree of burnup of the fuel, and the reactivity coefficients, were not studied. The results of such comparative investigations were first published in [1]. In th e present paper, multigroup calculations of the burnup and fission rate, i.e., the elimination of Np, Am, Cm, and their daughter nuclei during irradiation in different neutron fluxes and spectra, are presented. In addition, the latest data on the radiation safety standards are used [2] and the list of possible transmutation reactors and Np, Am, and Cm sources is expanded. The combined approach to handling long-lived radionuclides using transmutation and long-term storage is analyzed. The results obtained made it possible to choose the optimal, in our opinion, scenario for transmutation of Np, Am, and Cm.