The lectures reported in these proceedings were given in the Workshop on Nuclear Reactors — Physics, Design and Safety held at the International Centre for Theoretical Physics in Trieste in 1994 by experts from leading international research institutions and industries. They have been organized in a self-consistent form with the objective of giving basic, up-dated information to scientists and engineers from developing countries in modern methods for the computation and analysis of nuclear reactors, with particular emphasis on reactor physics, design and safety.