Implementation of ISO 14001:2004 (environmental management system) has been executed for reverse osmosis desalination plants for the first time in Iran at Noor Vijeh Company (N.V. Co), a water and wastewater firm based in Tehran. The scope of work was the activities and product of company's BWRO desalination plant in the city of Qom (3000 m(3) per day) and SWRO desalination plant in Assaluyeh, Pars Special Economic and Energy Zone, Iran. The aims of this project were in line with company's approach to sustainable development and its direction towards conducting environmental friendly activities and production characteristics. Initially the famous PDCA (Plan, Do, Check, Act) was used to identify the aspects and evaluate their effects. The significant aspects of each plant affecting the environment are then identified and preventive control measures and reducing their probabilities of loss are anticipated. These cover the normal activities within each plant and those aspects arising from emergency conditions such as earthquakes, fire, etc. Elements of this system are Environmental policy and its targets and programmes Practical methods for environmental management system processes Executive manuals for implementing special activities Tables and indexes for environmental aspects for each plant Organizational charts, positions, qualifications, and necessary trainings for the involved personnel. Environmental aspects are evaluated through their interaction with and effects over, releases to water, emissions to air, land contamination, waste management, energy use, and use of natural resources and raw material.