Based on negative trends like climate change, dwindling resources, pollution of air and soil or social grievances, more attention is paid to sustainability. Nowadays there is already a common accordance among society, politicians and academics that companies have the power to contribute to sustainable development by changing their business model towards a more sustainable one. Within the scientific literature, the business model concept has received lots of attention in recent years and sustainable business models get more relevant, even though there is a lack of definition about this concept. But it is evident that only a holistic integration of sustainability into the companys business model is meaningful. Therefore, this thesis aims to answer the questions about how business models are changing due to the rising importance of sustainability, what are influencing factors for this transition process, as well as which barriers might hinder companies in the transition towards a business model for sustainability (BMfS) and what are the drivers that promote changing the business model. Furthermore, the role of relevant stakeholders during the transition is investigated. Therefore, theoretical and empirical research is conducted. Theoretical research is based on the analysis of scientific literature dealing with the concept of business models and business strategy, the change of business models, and finally of linking sustainability to the concept of business models to deal with BMfS. The empirical part consists of qualitative, interview-based case studies about Austrian companies that successfully have changed their business model. The results show that BMfS are likely to be the future of our economy, even though the transition is a slow and difficult process, which needs to overcome barriers like the lack of resources. But the drivers, like a more efficient value chain, predominate.