While nuclear energy has still not gained significant social acceptance due to fear of safety and issues related to nuclear waste, in recent years nuclear industry continue to improve nuclear power development methods with novel approaches. This chapter examines some of these novel approaches. Third generation of nuclear reactors is being commercialized globally. The chapter briefly presents global progress in this direction. Seven fourth generation of nuclear reactors that are being developed globally is also reviewed in this chapter. These reactors are aimed at improving the efficiency of nuclear heat to power by increasing operating temperature and novel methods of capturing and controlling high-temperature nuclear heat. The chapter also examines a novel fourth-generation reactor developed by Terra Power industry who has strong financial and political backings. The improvement of heat to power conversion efficiency using a supercritical CO2 cycle is also analyzed. Recently significant efforts are also made to develop small modular reactors. The chapter reviews the global landscape of SMR. The chapter also considers other advances made in the use of nuclear power and nuclear energy in general. One important area has been the use of nano technology to improve water usage of nuclear reactor and improve material aspects of nuclear power plant. Nano technology has made other impacts such as in the areas of nano-fuel, reactor cooling, nuclear waste disposal, radiation resistance etc. The chapter evaluates these advances in some details. Finally, the chapter briefly examines the methods for the direct conversion of radioisotope heat source to electricity.