The book is devoted to investigation of a series of problems of convective heat and mass transfer in rotating-disk systems. Such systems are widespread in scientific and engineering applications. As examples from the practical area, one can mention gas turbine and computer engineering, disk brakes of automobiles, rotating-disk air cleaners, systems of microclimate, extractors, dispensers of liquids, evaporators, c- cular saws, medical equipment, food process engineering, etc. Among the scientific applications, it is necessary to point out rotating-disk electrodes used for experim- tal determination of the diffusion coefficient in electrolytes. The system consisting of a fixed disk and a rotating cone that touches the disk by its vertex is widely used for measurement of the viscosity coefficient of liquids. For time being, large volume of experimental and computational data on par- eters of fluid flow, heat and mass transfer in different types of rotating-disk systems have been accumulated, and different theoretical approaches to their simulation have been developed. This obviously causes a need of systematization and generalization of these data in a book form.