Th. S. Leifsson graduated from the University of Iceland in 1980 with a BS degree in Civil Engineering, and with M.Sc. degree from Colorado State University in 1982, specializing in hydraulics and hydrology. He worked as a consulting engineer for Almenna Consulting Engineers in Iceland from 1982 to 2002 and for VST/VERKÍS since 2002, notably in the field of hydro¬power development, planning and hydraulic engineering. He was a member of the Hydraulics Team within the Kárahnjúkar Engineer¬ing Joint Venture (KEJV) and participated in most of the hydraulic tasks in the design of that project. He has for over 40 years worked on feasibility studies, hydraulic design and optimization of most of the hydropower projects constructed in Iceland, and on various international projects.