This comprehensive, handbook-style survey of diffusion in condensed matter gives detailed insight into diffusion as the process of particle transport due to stochastic movement, which is understood and presented as a phenomenon of crucial relevance for a large variety of processes and materials. In this book all aspects of theoretical fundamentals, experimental techniques, highlights of current developments and results for solids, liquids and interfaces are presented. Students and scientists in physics, chemistry, materials sciences and biology will benefit from this detailed compilation.