Extensive experimental studies showed that thin-film, composite membranes can be used effectively for the separation of selected hazardous organic compounds. This waste treatment technique offers definite advantages in terms of high solute separations at low pressures (<2MPa) and broad pH operating range, and the use of charged membranes would allow the selective separation of some organics from feeds containing high salt concentrations. In addition, feed pre-ozonation of selected organics provided significant improvement in flux and rejection characteristics for both charged and uncharged membranes because of the formation of ionizable organic acid intermediates during the ozonation that did not interact as strongly with the membrane. The overall ozonation/membrane process effectively produced permeate water of high quality while it minimized the volume of waste that must be further treated.