The utilization of sustainable and high-performance technologies is a growing tendency in industrial processes. The membrane separation process is a clean technology alternative that can be used to separate, concentrate, and/or purify substances. But there is still a great interest in turning this process increasingly sustainable by the structural modification of the membranes using biopolymers and green solvents, and the functionalization with organic and inorganic materials, also improving their performance and anti-fouling characteristics. Thus, this review chapter brings the main concepts about membranes and their main structural modifications to obtain a process that meets the concepts involved in Green Technology.