Natural rubber bearing were first used for the earthquake protection of buildings in 1969 for the Pestalozzi school in Skopje, Macedonia.The bearings are large rubber blocks without the steel reinforcing plates used today and compress by about 25% under the weight of the building. The bearings have a vertical stiffness that is only a few times the horizontal stiffness and the rubber is relatively undamped. This system was tested on the shake table at the EERC in 1982. Characteristic of isolation systems of this kind, the horizontal motion is strongly coupled to a rocking motion, so that purely horizontal ground motion induces vertical accelerations in the rocking mode. The system also has foam-glass blocks on either side of a rubber bearing that are intended to act as fuses to prevent movement in the building under wind, internal foot traffic, or low seismic input. The system is still in place and is monitored from time to timeSince thus building was completed, many other buildings have been built on natural rubber bearings but with internal steel reinforcing plates that reduce the lateral bulging of the bearings and increase the vertical stiffness. The internal steel plates, referred to as shims, provide a vertical stiffness that is several hundred times the horizontal stiffness, these multilayered elastomer bearings provide vibration isolation for apartment blocks, hospitals and concert halls built over subway lines or mainline railroads. In 1975 derham et al. suggested that this approach could be used to protect building from earthquake ground motion, and a intensive experimental and theoretical research program was begun at the EERC to develop this concept. Laminated elastomeric bearings can be differentiated into low-damping or high-damping types