The concept of dam construction is very ancient and mainly served a basic human need,gradually becoming a multi-purpose structure. It has been argued that global climate change as well as variations in precipitation patterns and its uneven distribution have increased the need for the development of dams&reservoirs because of the increased demand for water storage.Therfore, dam development which goes back thousands of years, can play a significant role in water resources management.Nevertheless, dams & reservoirs are controversial due to their high upfront investment and their social & environmental impacts, and also in some cases dams are disaster-prone structures in terms of their failure. Thus, looking at past experiences in dam planning and construction can teach unique lessons for improving the governance of large infrastructures and enhancing dam safety. The high costs of dam building & the uncountable price of dam failure have driven the dam industry to draw important lessons from dam failure events. One of the saddest events but most valuable in terms of lessons offered for progressing in dam safety standards,has probably been the failure of the Vajont Dam in Italy in 1963.