Diffusion: Introduction and Case Studies in Metals and Binary Alloys -- The Elementary Diffusion Step in Metals Studied by the Interference of Gamma-Rays, X-Rays and Neutrons -- Diffusion Studies of Solids by Quasielastic Neutron Scattering -- Diffusion in Semiconductors -- Diffusion in Oxides -- Diffusion in Metallic Glasses and Supercooled Melts -- Fluctuations and Growth Phenomena in Surface Diffusion -- Grain Boundary Diffusion in Metals -- NMR and ?-NMR Studies of Diffusion in Interface-Dominated and Disordered Solids -- PFG NMR Studies of Anomalous Diffusion -- Diffusion Measurements by Ultrasonics -- Diffusion in Membranes -- Viscoelasticity and Microscopic Motion in Dense Polymer Systems -- The Molecular Description of Mutual Diffusion Processes in Liquid Mixtures -- Diffusion Measurements in Fluids by Dynamic Light Scattering -- Diffusion in Colloidal and Polymeric Systems -- Field-Assisted Diffusion Studied by Electrophoretic NMR -- Diffusion of Particles on Lattices -- Diffusion on Fractals -- Ionic Transport in Disordered Materials -- Concept of Mismatch and Relaxation for Self-Diffusion and Conduction in Ionic Materials with Disordered Structures -- Diffusion and Conduction in Percolation Systems -- Statistical Theory and Molecular Dynamics of Diffusion in Zeolites.Diffusion as the process of particle transport due to stochastic movement is a phenomenon of crucial relevance for a large variety of processes and materials. 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. Leading experts in the field describe in 23 chapters the different aspects of diffusion, covering microscopic and macroscopic experimental techniques and exemplary results for various classes of solids, liquids and interfaces as well as several theoretical concepts and models. Students and scientists in physics, chemistry, materials science, and biology will benefit from this detailed compilation.