An important contribution to the realization of industrial sustainable development can be given by “green process engineering”. Based on the principles of the Process intensification strategy it can lead to the development and the re-design of new processes more compact and efficient that allow the better exploitation of raw materials, a lower energy consumption and a reduced plant volume. Membrane technology contributes to the pursuit of these principles and, in the last few years, the potentialities of membrane operations have been widely recognized. In this work, an overview of membrane application and their perspectives in the field of hydrogen production and distillation will be analysed considering membrane reactors and membrane distillation as case studies. The scope is to show how the redesign as membrane systems of traditional operations might contribute to the realization of the goals of process intensification and green chemistry by a new “green process engineering”.