Membrane based filtration and separation technologies offer energy-efficient solutions for a wide range of applications, from clean water technology to chemical manufacturing, the petroleum industry and carbon emission control. With the current global energy and water challenges and the emergence of nanomaterials, membrane based separation is attracting ever-increasing interests from both academic societies and industries. Recent innovations in membrane materials have provided great enhancements for separation performance, which has led to the next-generation membrane based separation technologies. In this chapter, the development of a wide variety of separation technologies has been reviewed with the emphasis on membrane materials. Nanofiltration and desalination have been highlighted with the recent advances in nanomaterials-enabled, in particular graphene based, advanced membranes.