All the Arabian Gulf States suffer from a shortage of fresh water resources. This deficiency is remedied through the desalination of seawater, mainly by the multi- stage flash (MSF) evaporation technique. The number of MSF distillers in Abu Dhabi is 382, producing a total quantity of 5,465,784 m(3)/d of potable water. It has been reported that these units have a tendency to suffer, at varying degrees, from a variety of corrosion and scaling problems. This paper consists of two sections. The first section describes some of the corrosion problems facing the desalination plants, concentrating mainly on the vapour-side corrosion (VSC) of condenser tubes made of cupronickel alloys, 70/30 and 90/10. The research in this section is necessary because condenser tubes are the part most prone to failure in desalination plants. Almost all of the previous cases of corrosion of condenser tubes reported were focused on water-side corrosion of the tubes. The present paper will discuss two contrasting cases of attack related to both acidic and alkaline corrosion in the vapour side. This is the first such research to be cited anywhere in this field. The second section of the paper will discuss the mechanism of the scale formation reported in the literature, and will present the actual scale formed in desalination plants, which is different from scale formed in the laboratory.