Since ancient times, humans have mobilized huge efforts to counter water shortages and meet water demands in arid and semiarid areas. If, however, water issues existed on a local scale in the past, in the present and future these problems occur on national, regional, and global scales and could threaten peace keeping, food security, and eventually sustainable development. In Iran, a nation covering about 1,650,000 km(2), the supply, transfer, and use of water are major concerns, just as they were in ancient times. At present, about 55% of the water consumed in Iran is provided from groundwater resources and 45% from surface water, and more than 90% of water resources are allocated to the agriculture sector. The freshwater shortage has caused an increase in saltwater consumption, especially in arid and semiarid zones. Misuse and unrestrained water resources arid traditional irrigation systems have caused soil salinity, land degradation, arid desertification problems. Increasing salinity in most water resources in Iran over the past 10 years has caused ail intensive decline of soil arid water quality. Therefore, one of the main economical and social strategies of the government of Iran must be management that optimizes the use of water resources to attain sustainable development.