With the growing demand for affordable energy and concerns about the environment, there is a renaissance underway in fundamental actinide science, underpinning the development of materials, fuels, waste forms, and separation technologies for nuclear energy. Actinide materials pose an extreme scientific challenge to the materials research community. The complex electronic structure of actinides results in many abnormal properties that even today are not well understood, if at all. The focus of this book, the fourth in a continuing series, is on fundamental actinide science and its role in resolving technical challenges posed by actinides materials. Both basic and applied experimental approaches, as well as theoretical modeling and computational simulation, are featured. Topic include: phase transformation and metallurgy; electron correlations and structure; nuclear fuel, waste and storage; actinide chemistry; spectroscopy and microscopy of actinides; atomistic modeling; and superconductivity and complex behavior.