The pre-study aims to increase knowledge about what is required for small and medium-sized enterprises (SMEs) to transition to circular business models. The pre-study will also create collaborations and increase knowledge about circular economy among SMEs in Eskilstuna and further develop ReTuna as a test bed for circular business concepts. The aim is also to find at least five SMEs that in a future project can use ReTuna as a test bed for their circular business models.