It is an undisputed reality that the energy production and, particularly, the production of electricity and their sustained growth, constitute indispensable elements for the economic and social progress of any country. Without any doubt, energy constitute the motive force of the civilisation and it determines, in a high degree, the level of economic and social development of a country. To ensure an adequate economic and social growth of a country, there is a need to use all available types of energy sources for electricity production, including nuclear energy. This book discusses the role of nuclear power in the world electricity generation.