Prof. Martin Saar is the chair of the Geothermal Energy and Geofluids (GEG) group in the Department of Earth Sciences at ETH Zurich, Switzerland. The GEG group investigates reactive subsurface multiphase, multicomponent fluid and energy transfer, addressing fundamental to applied research questions, such as groundwater and hydrocarbon flow, geologic CO₂ storage, and geothermal energy utilization - typically combining these topics in joint projects (see also talk title). The 30-researcher GEG group includes geoscientists from various fields and engineers as well as mathematicians and computer scientists, employing numerical, laboratory, and field techniques to tackle these research and often societal problems. Prof. Saar received his Pre-Diploma in 1995 in Geology from the University of Freiburg, Germany, his MSc. in 1998 in Geology from the University of Oregon, USA, and his Ph.D. in 2003 in Earth and Planetary Sciences (Geophysics) from UC Berkeley, USA. He was then the Turner Postdoctoral Fellow in 2003-2004 at the University of Michigan, USA, and then the Gibson Chair for Hydrogeology and Geofluids as well as a Geology and Geophysics Assistant, Associate, and eventually Full Professor at the University of Minnesota - Minneapolis, USA, from 2005 through 2014. Since 2015, he has been at ETH Zurich in Switzerland, where he founded the GEG group, which is endowed by the Werner Siemens Foundation. In 2018, Prof. Saar co-founded the company CO2 POWER with the mission to help implement CO₂-based geothermal power generation and district cooling as well as CO₂-based subsurface energy and permanent CO₂ storage, which may also promote enhanced oil/gas recovery. For more information, please visit the Geothermal Energy and Geofluids (GEG) group web site at: GEG.ethz.ch