This book contains a systematic investigation of the convection in systems with interfaces. For the first time, it classifies all of the known types of convective instabilities in such systems, and discusses the peculiarities of multilayer systems. The book provides an overview of the wide variety of steady and oscillatory patterns, waves, and other dynamic phenomena characteristic for multilayer fluid systems. Various physical effects, including heat and mass transfer, thermal and mechanical couplings on the interfaces, interfacial deformability, the influence of surfactants on different types of convective motions are investigated. The text will be useful for researchers and graduate students in fluid mechanics, nonlinear dynamics and applied mathematics as well as for physicists and chemical engineers interested in the investigation of the interfacial physico-chemical processes and in their applications.