Recent literature has recognized the difficulty of implementing Circular Economy (CE) in supply chains. This has not yet led to a clear understanding of the reasons. This is critical to address, because the difficulty stalls the CE transition and suspends its benefits. Therefore, this paper investigates the reasons for the difficulty of implementing CE in supply chains. In so doing the Dutch stony materials supply chain is used as empirical case. Through a literature review, the role of changes and responsibilities in CE implementations inside the supply chain, has been gained. Based on these insights, a Social Network Analysis approach for capturing and analysing perceptions of supply chain actors on the CE changes was developed. The findings show that the diffusion of responsibility and differences of perceptions are underlying reasons of the difficulty to implement CE in supply chains. The main reasons for these two developments consists of: (1) Lack of incentives for the supply chain actors to make a change towards circularity; (3) Lack of mutual interests between supply chain actors; (2) High uncertainties and risks and (4) Clashes of perceptions on all levels in supply chains. It was found that the observed diffusion of responsibility was due to the individual pursuance of the changes that benefit individual business models and making parties responsible for these changes if they have the biggest impact on their business. As long as supply chains are voluntarily changing, this will stall the transition, some obligatory outside influence can refine the incentives to change.@en