Much of my current research interests are in the properties of two-fluid boundary layers, with applications ranging from airplane and helicopter performance in adverse weather conditions to technological and natural processes. Perturbation theory and numerical computations are used as the main tools. The theory has potential to include heat transfer, condensation, icing and multiphase flows. Another branch of my research is related to instability, receptivity and laminar-turbulent transition in two- and three-dimensional, steady and unsteady flows.