To maintain alignment with technology, regulation and market developments in the outside world, companies need to adapt their business models over time. As most literature has studied business models in a static approach, understanding is lacking on how external forces drive internal business model design choices. This paper studies which type of external drivers are most influential throughout the life cycle of business models. To do so, we surveyed 45 longitudinal case descriptions on business model dynamics of (networks of) organizations in various domains. Our results partly support our hypotheses. Market and technology drivers are most relevant in early stages of new business models, while regulation is far less important than we expected. These results mainly apply to small start-ups rather than large, established companies.