The general non equilibrium statistical approach, due to Zubarev, is presented briefly in Chapter 1. Chapter 2 is devoted to construction of an application of this approach to a statistical mechanical description of transport processes on a dividing surface between two immiscible fluids when singular densities of mass, and/or momentum, and/or energy are presented. In chapter 3 the shock wave in a gas is considered an interphase boundary of the gas-gas type. Chapters 4 and 5 fluctuations of flows of mass or momentum across the surfaces of sufficiently small liquid or solid particles, respectively, are discussed. Finally, chapter 6 discusses a generalization of the one-particle Brownian motion theory to many-particle situations, where the interparticle hydrodynamic ineraction are essential.