The book deals with an important and complex issue in geotechnical and earthquake engineering, which concerns the influence of both plasticity and pore water pressure on the influence of the seismic response to real earthquake records. Analyses are carried using the software FLAC3D. The book includes three parts: The first chapter presents a literature review of research on earth dams. It presents observation during earthquake loading, the different methods of seismic analysis of earth dams, such as the simplified methods, the empirical methods, the equivalent-linear analyses and the non linear methods. The second chapter presents a numerical analysis of the seismic behaviour of earth dams. Analysis is conducted for the solid phase. It corresponds to the response of the dam before water filling. The third chapter presents a numerical analysis of the influence of the water-skeleton interaction on the response of earth dams to seismic loading. Analysis is conducted first under undrained condition, which corresponds to a simplified analysis of the response of the dam.