Most of the seismic energy during earthquakes is carried by body elastic waves in the Earth’s lithosphere. Usually body waves have little impact to man-made constructions on the ground. Body elastic waves could have some effect only on deep underground constructions such as tunnels, dams, and gas or oil lines. Their impact is mostly through their conversions into surface elastic waves. Since most of buildings, highways, power stations, bridges and other man-made constructions are located above the ground surfaces elastic waves generated by bulk elastic waves are of greatest importance. There are various types of surface elastic waves that originate from body waves. In this section we will discuss how they are excited and how they propagate as well as their linear and nonlinear properties.