Diffusion-controlled processes still remain the most important and interesting phenomena in materials science. Among the problems which are currently to the fore, are the synergy of diffusion and morphological evolution, the initial stages of solid-state reactions, the analysis of nano-materials and related phenomena, thermo- and electromigration, and the reliability of solder joints and interconnects in microelectronic devices. A number of challenging problems still remain within the 'classical' areas of nucleation, reactive- and inter-diffusion, phase growth in multicomponent and binary systems, and decomposition and ripening.These aspects are reflected in the 32 peer-reviewed papers which are to be found in this volume under the headings of: Diffusion and Reactions, Driven Systems, General Problems of Diffusion, and Structural & Phase Transformations.