Elected member of the Polish Academy of Sciences, Director of the M. Nalecz Institute of Biocybernetics and Biomedical Engineering, Head of the Biophysical Measurements Laboratory and the Department of Biophysical Imaging and Measurements at the IBIB PAN, member of the International Academy of Medical and Biological Engineering (IAMBE). He received his M.Sc. degree from the Faculty of Precision Mechanics, Warsaw University of Technology, and his Ph.D. and post-doctoral degree in technical sciences in Biocybernetics and Biomedical Engineering from the Institute of Biocybernetics and Biomedical Engineering of the Polish Academy of Sciences (IBIB PAN). From 2001 to 2004, he completed a postdoctoral fellowship at the Physikalisch-Technische Bundesanstalt in Berlin at the Department of Medical Physics and Metrological Information Technology. Since 2014, he has been the Director of the Nalecz Institute of Biocybernetics and Biomedical Engineering of the Polish Academy of Sciences. He is a founding member of the Polish Society for Biomedical Engineering. He has served as Chairman of the Committee on Biocybernetics and Biomedical Engineering of the Polish Academy of Sciences since 2020. Prof. Liebert is an expert of the European Research Council, NCN, NCBiR and the Academy of Finland for the evaluation of scientific research projects in the field of biomedical engineering. He is an editor in the journals Opto-Electronics Review and Bulletin of the Technical Sciences of the Polish Academy of Sciences and a member of the editorial board of the Journal Technology and Health Care. His research activities are related to tissue optics, assessment of light-tissue interactions and the application of optics and photonics in biomedical measurements.