Stefan Klein is Associate-Professor in Medical Image Analysis and is heading the Image Registration research line. He is affiliated with the Biomedical Imaging Group Rotterdam (BIGR, http://www.bigr.nl), Departments of Radiology and Medical Informatics. In 2002, Stefan received his MSc degree from the faculty of Mechanical Engineering at the University of Twente, Enschede/NL. In 2008 he obtained his PhD degree at the Image Sciences Institute, UMC Utrecht/NL, for his research on optimisation methods for medical image registration. In 2010, He received an NWO Physical Sciences VENI fellowship. He is co-principal developer of a widely used open source software package for medical image registration, called Elastix (http://elastix.isi.uu.nl) and was general chair of the WBIR2018 conference. His current research interests include image reconstruction, radiomics, and disease progression modelling.