Michael Ljungberg is a Professor at Medical Radiation Physics, Lund, Lund University, Sweden. He started his research in the Monte Carlo field in 1983 through a project involving a simulation of whole-body counters but later changed the focus to more general applications in nuclear medicine imaging and Single Photon Emission Computed Tomography (SPECT). As a parallel to his development of the Monte Carlo code SIMIND, he started working in 1985 with quantitative SPECT and problems related to attenuation and scatter. After earning his PhD in 1990, he received a research assistant position that allowed him to continue developing SIMIND for quantitative SPECT applications and established successful collaborations with international research groups. At this time, the SIMIND program also became used worldwide. Dr. Ljungberg became an associate professor in 1994 and in 2005, after working clinically as a nuclear medicine medical physicist, received a full professorship in the Science Faculty at Lund University. He became head of the Department of Medical Radiation Physics in 2013 and a full professor in the Medical Faculty in 2015. Besides the development of SIMIND to include a new camera system with CZT detectors, his research includes an extensive project in oncological nuclear medicine and, with colleagues, he developed dosimetry methods based on quantitative SPECT, Monte-Carlo absorbed dose calculations, and methods for accurate 3D dose planning for internal radionuclide therapy. In recent years, his work has focused on implementing Monte-Carlo based image reconstruction in SIMIND. He is also involved in the undergraduate education of medical physicists and biomedical engineers and is supervising MSC and PhD students. In 2012, Professor Ljungberg became a member of the European Association of Nuclear Medicines task group on dosimetry and served in that group for six years. He has published over a hundred original papers, 18 conference proceedings, 18 books and book chapters and 14 peer- reviewed papers.