Recently, large numbers of high capacity TVC/MEB (multi-effect thermal vapor compression combined with conventinalmulti effect boiling) desalting units have been built or ordered in the UAE and elsewhere. An in-depth comparison between the predominantly used MSF and the TVC/MEB is conducted in this paper to show the reasons of this trend to used the newly used TVC/MEB units. The TVC/MEB units operate at lower top brine temperature TBT to limit the risk of scale formation and corrosion. This decreases the difference between TBT and last effect (stage) temperature Tn, and this tends toincrease the heat transfer surface area of the TVC/MEB; compared to the MSF system. However, the high heat transfer rates in film boiling in TVC/MEB evaporators keep the heat transfer area the same in both systems. Moreover, the TVC/MEB system has more merits copared to the MSF such as: it has better response to the variation of steam supply, less footprint area, less pumping energy, and the ability to operate at different modes than the design.