Due to the fast development of information technology, the understanding of phenomena in natural, engineer, economy and social sciences increasingly relies on computer simulations. Simulation-based analysis and engineering techniques are traditionally a research focus of Clausthal University of Technology and University of Göttingen, which is especially reflected in their common interdisciplinary research cluster “Simulation Science Center Clausthal-Göttingen”. In this context, the first “Clausthal-Göttingen International Workshop on Simulation Science” aims to bring together researchers and practitioners from both industry and academia to report on the latest advances in simulation science.