The interest in diffusion in solids is as old as physical metallurgy or materials science. It stems from application-oriented as well as from scientific reasons. First, a knowledge of diffusion is basic to an understanding of many microstructural changes that occur in solid matter at elevated temperatures. For processes like phase transformations, precipitation or dissolution of a second phase, recrystallization, oxidation, creep, annealing etc., solid state diffusion is fundamental and ubiquitous. The second reason for studying diffusion is to learn more about how atoms move in solid matter. Volume III/26 presents for the first time a comprehensive collection of diffusion data for solid metals and alloys. The critical compilation of data has resulted in tables and series of diagrams which show in 13 chapters data for the following properties: Self- and impurity-diffusion in metallic elements, self-diffusion in homogeneous binary alloys, chemical diffusion in binary and ternary alloys, diffusion in amorphous alloys, diffusion of interstitial foreign atoms like hydrogen, carbon, oxygen and nitrogen in metallic elements, mass and pressure dependence of diffusion, diffusion along dislocations, grain and interphase boundary diffusion, and diffusion on surfaces.