The state of the art in membrane-based separation ofoptical isomers has been reviewed.A molecular recognition in such processes is provided by chiral environment in a membrane phase or by soluble chiral selector (CS) preferentially binding one of isomers. The principles and potentialities of chiral separations based on CS rejection by membrane (complexation/ultrafiltration), CS transportation through the membrane (membrane extraction), and CS inclusion into the membrane phase (liquid membrane) have been discussed. Data on development of membranes for the molecular recognition of optical isomers and membrane mass-transfer during enantiomer separation have been analysed. The chiral separation in membrane reactors with CS as a catalyst of enantiomer transformation has been discussed.