Since the visual confirmation of deep seafloor hot springs, or hydrothermal vents, at the Galapagos Rift in 1977, submarine hydrothermal activity has been studied in all ocean basins, at a wide range in depth, and in a variety of volcanic and tectonic settings. In 2004 Baker and German undertook a review of the global distribution of hydrothermal vent fields (in Mid-Ocean Ridges: Hydrothermal Interactions Between the Lithosphere and Oceans, Geophysical Monograph Series 148, German, C.R. et al., eds., 245-266). As InterRidge Coordinator, Beaulieu combined Baker’s global listings of vent fields with several other listings, incorporated new findings including from commercial industry, and in 2010 released the revised InterRidge Global Database of Active Submarine Hydrothermal Vent Fields (http://www.interridge.org/IRvents). The database provides a comprehensive listing of confirmed (visually, from seafloor observations) and inferred (based on water column measurements and/or seafloor sampling) active hydrothermal fields. As of the end of 2009, there were 229 confirmed active submarine hydrothermal vent fields, with 47% at mid-ocean ridges, 27% at volcanic arcs, 21% at back-arc spreading centers, and 5% intra-plate and other tectonic settings. Thirty-five percent of the confirmed active vent fields were confirmed in the decade 2000-2009, with a relatively large number of these at volcanic arcs. The total number of inferred active vent fields at the end of 2009 was 273, more than double the number in Baker and German (2004) and reflective of the increased efforts in systematic surveys for detection of hydrothermal plumes. Although many of the recent discoveries were made by academic researchers, an increasing number of discoveries are due to national and commercial interests in seafloor mineral exploration.