Over the past few decades computer simulations have attained an ever-growing importance in many scientific disciplines. Recently, scholars have started debating the wider philosophical, cultural and social aspects of this historical development. Despite the increasing wealth of literature on the subject, surprisingly few case studies exist, which explore the many ways and historical trajectories of computational methods in general and computer simulations in particular. In my work I explore case studies in different fields of the biological sciences and their use of simulations. In particular, I am interested in the use of simulations to conceptualize and depict organic processes and motion. Recent developments in the biomedical sciences suggest that research into motion has been gaining increasing attention for the last 50 years or so. Cell motility, for example, is of central importance here. Research on cell motility has emerged in various fields, such as microbiology (amoeba), physiology and immunology (leucocytes), embryology (cell migration during morphogenesis), cancer research (metastasis) and wound healing and regeneration (fibroblasts). The project investigates the role and function of simulation in the biological endeavor to understand biological processes. Can we apply our existing battery of analytic tools to the study of simulation-based science? Are simulations merely a technologically sophisticated tool for modeling or rather an alternative (virtual) form of an experimental system? Existing scholarship tends to concentrate on the relation between simulation and ‘models’, as well as on the validity of computer-based simulations as a source for prediction/prognosis and testing/proof. At the same time, the use of computer simulation in biology is as vast as it is diverse. With the help of case studies the project aims at investigating in detail recent uses of simulations and their relation to tools and devices previously employed in various fields. A research interlude at the KLI would enable me not only to discuss the case studies and the epistemological status of simulations in biology but also to engage with the biologists in residence in order to learn from their practices and experiences.