An extensive review of case histories of embankment dam behavior during earthquake was undertaken after several major embankment dams were severely shaken by the 1990 Philippines earthquake. The objectives of the study, which continues to date, were to determine if there is a “normal” trend of seismic deformation that can be predicted and if there are certain factors that consistently have an effect on the amount of damage and deformation incurred during earthquakes. Nearly 70 case histories have been reviewed, compared and statistically analyzed in this effort. The results of this empirical study have shown that the most important factors that appear to affect dam crest settlement during earthquake include the peak ground acceleration at the site and the earthquake magnitude. A chart has been prepared to summarize the relationship between the amount of measured settlement and the peak ground accelerations experienced in the incidents that were studied. In addition, an empirical equation was formulated and a graph developed as an aid in estimating the amount of deformation to be expected.