Kuwait Institute for Scientific Research (KISR) and the Ministry of Electricity and Water (MEW) collaborated over the past 15 years in developing and adapting the seawater reverse osmosis (RO) technology to the Gulf seawater conditions (one and half time the salinity of open seas and large temperature variations between summer and winter in the range of 35 degreesC and 10 degreesC, respectively), The development process went through several stages involving performance evaluation of three types of membrane configurations under various operating conditions and using different types of feed water pretreatment techniques. It went also through the evaluation of various commercially available energy recovery systems and the development of a new system. During this period, the RO research program evaluated the performance of ten different seawater membranes, cleaning and restoration techniques and procedures, using various potential agents. Furthermore, computer aided design program and process design and optimization procedures were developed specifically for Gulf seawater conditions, The studies also involved two-phase evaluation of multistage flash/reverse osmosis (MSF/RO) hybrid systems, Cost assessment of product water from RO under different operating conditions and various system configurations was always an important integrated part of each research project.