Zero Liquid Discharge (ZLD) is an emerging engineering technology of water treatment. In general, most of the treatment processes attempt to maximize the recovery of freshwater and minimize waste. The primary procedures to achieve ZLD systems are through employment of various pre-treatment technologies such as, reverse osmosis, crystallization, distillation, etc. After proper treatments, it is possible to reuse the salt and other compounds generated as solid wastes from the highly concentrated brine solutions. Studies suggest above 95% of freshwater resource recovery from ZLD systems. Although it is a costly process, it significantly promotes sustainability and paves the way for circular economic goals.