Since 1903 when good instrumented data first became available over 100 great earthquakes of Richter Magnitude 8.0 or greater have occurred in the world. Many of the high seismicity zones in the world are in locations of large astronomical observatories. These include Chile, California, Hawaii and Japan. When building new observatories it is necessary to provide seismic protection in case an earthquake does occur. It is also important to reevaluate existing facilities to determine if they are adequately protected according to the latest engineering practice. This paper relates the locations of the world's major observatories, particularly those in the United States, to the earthquake hazards in these areas. Instances of damage to instruments during earthquakes will be numerated. Criteria for designing facilities to resist earthquake loads will be summarized, and certain protection techniques will be presented.