Treating effluents - industrial as well as domestic - is an area which needs concerted effort and serious attention. We need to deepen our understanding of what membranes can do taking into consideration the extremes of operation and complex effluent characteristics. Nanofiltration has proved effective in color removal of textile effluents and in pharmaceuticals, where 90% removal is reported and widely practiced. Successful case studies are presented along with revamp projects. In the case of RO, which is the tightest of separation techniques for water and non-water streams, use of fouling resistant (FR) and high surface area elements is emphasized. Technological limitations on case by case basis vis-a-vis RO/NF/UF/MF/ED is widely discussed. Modularization technology leading to reduction in running and installation costs is strongly advocated. Newer membrane materials are touched upon driven more by application rather than system specific. Industrial effluents and sewage constitute a major chunk of recycle operations to the extent of 65% in some countries. In one such city sewage RO plant, the operational cost has been reduced to 31% by retrofitting the pre-treatment section. Some of the Mega SWRO plants in the Middle East have gone into demo-UF plants. The arsenic contamination in major available resources of third world countries has reached alarming proportions. Technoeconomic viable solutions vis-a-vis available membrane operations are suggested.