People tend to live in large cities close to volcanoes. In the past, this connection was a result of the fertile soils, water supplies, and cultural-historical sites provided by volcanoes. Today, the most important link comes from peoples’ preferences to live at or near coastlines, where more than half of the Earth’s active volcanoes are concentrated. Volcanoes literally create new real estate, by building land above sea level. They also provide natural harbors and fortifications, tourist attractions, geothermal energy, mineral resources, and water supplies from crater lakes and from mountain snow and rain. One out of twelve humans lives within the danger zone of an active volcano. However, even an “active” volcano can be quiet for hundreds, even thousands, of years between eruptions. Do the long-term benefits of living near a volcano outweigh the risks? People can only answer this question if they understand the hazards and if they can be assured of warning early enough to save their lives, if not their property, by moving away in time.