Dams construction is an old art practiced by man since thousands of years. History of dams shows great innovations in this field, but failure cases, however, indicate gaps in human knowledge of safety measures that could have stopped such failures. Available statistics show of a great boom in building dams during the past century and indicate at the same time large number of failures associated with losses in human lives and material damage. Uses of these dams during this period, apart from flood control and storing water for irrigation were also for hydropower generation, navigation, drinking water supply, recreation and in mining operations as tailing dams. Reduced dam safety leading to failures, accidents and higher safety hazards were caused by insufficient knowledge of the geological conditions and in using wrong or deficient foundation treatment. Dam safety was compromised in cases of insufficient hydrological data and design of inadequate spillways. Misinterpretation of the seismic conditions of the area and adopting seismic criteria compatible with such seismic conditions is also added as one more reasons of failures. Human mistakes and errors have undermined safety in many cases in the operation of dams leading to grave safety issues including many failures. Safety hazards also were exasperated by increasing population and land use in the downstream areas of dams and by failing to do necessary inspection and maintenance or upgrading works.  More emphasis over  dam safety measures is needed now in our existing dams and in their future development of dams if they are to continue delivering their benefit without causing harm to human communities.