Reverse Osmosis based Desalination Systems involve three liquid streams such as saline feed water, low-salinity product water and very saline concentrate. These Desalination Systems separate water from dissolved salts in pressurized saline solution by making it flow through a water-permeable membrane. These Desalination Systems operate on the pressure range from 250 to 400 PSI for brackish water desalination and from 800 to 1000 PSI for seawater desalination. These Reverse Osmosis based Desalination Systems are suitable for most domestic, industrial as well as agricultural uses.