As many major slope failures have occurred
 during medium and strong earthquakes, the
 assessment of the seismic stability of slopes in earthquake-prone areas is of great concern to engineers. Prior to 1964, little attention was
given to the development of rational aseismic
 design methods for earth slopes. Most design
 methods were based on a static analysis used 
in conjunction with an arbitrarily selected
 lateral force acting on the slope with soil
 strengths determined by conventional laboratory
 tests. However, the catastrophic slope failures
 which occurred during the Alaskan earthquake of 1964, resulted in a considerable reappraisal of
 such static design methods. In recent years
 significant progress has been made in developing 
new methods of laboratory testing to determine dynamic soil properties, improved techniques of analysing the dynamic response of slopes and embankments to earthquakes, and new concepts of aseismic design methods for earth slopes. Although research has yet to provide all the answers, the current state of knowledge at least provides an improved guide to engineering judgement in the assessment of the stability of earth slopes during earthquakes.