In the late 18th century, Neptunists and Plutonists had controversial opinions about the formation of the Earth and its lithological units. The former believed that rocks formed from the crystallization of minerals in the early Earth's oceans, the latter believed that rocks were formed in fire. Both theories ignored the importance of continuous water-rock interaction processes at Earth's surface and underground, which can enhance and define the type of volcanic activity, can cause the formation of secondary hydrothermal minerals and respective ore deposits, or simply alter the natural landscape by weathering. Although not visible at first glance, water-rock interaction plays a significant role in the daily life of humans.
Since 1974, when the first Water-Rock Interaction Symposia (WRI-1) was held in Prague (Czechoslovakia, now the Czech Republic), the Working Group on Water-Rock Interaction of the International Association of GeoChemistry (IAGC) has organized an international meeting every three years to present and discuss the most recent results in geochemical technologies. In 2010, WRI-13 attracted about 300 geoscientists affiliated with universities, research institutions, regulatory agencies and from private industry, from 35 countries to Guanajuato, Mexico. The 231 papers published in this volume describe novel advances in research related to interactive processes between the hydrosphere and the lithosphere.