Witold Trzeciakowski was born in Warsaw, Poland in 1952. He obtained M.Sc. degree in Solid-State Physics, Warsaw University in 1974. He received his Ph.D. at the Faculty of Physics, Warsaw University in 1980. In 1989 he received the degree of "habilitation" from the Institute of Physics, Polish Academy of Sciences and in 2000 the title of Professor of Physics. He worked from 1974 till 1980 as a teaching assistant at the Faculty of Physics, Warsaw University and then moved to the Institute of High Pressure Physics, Polish Academy of Sciences where he has been working until now. In 1983 he spent a few months at the High Magnetic Field Laboratory in Grenoble (France), in 1986-1988 he worked as a research associate at the National Research Council (Ottawa, Canada), in 1989 he spent 3 months at State University of New York (Buffalo, USA), in 1991-1992 at the LENS laboratory at the University of Florence (Italy), in 1993-1994 at the IXL laboratory of the Bordeaux University (France) and in 1996-1997 he was a visiting professor at the Department of Physics, University of Valencia (Spain). He participated in two European Projects and in one NATO research project. His main scientific activity was in semiconductor physics, both theoretical and experimental. His recent research concerned laser diode physics, including using pressure for wavelength tuning, and the application of laser diodes in dermatology.