A transition towards a circular economy (CE) is urgent, since the current economy depletes the earth and is too polluting. In the CE the aim is to reduce waste, maintain value of materials and products, and reduce the need for new raw materials. The Dutch government set the target to have a full circular economy by 2050. This shift towards CE brings new challenges. Companies will have to manage the return of products and materials. Typical complications in reverse logistics are low processing volumes, scattered collection, difficult processing, and uncertainty in the quality and quantity of returned goods. This research aims to develop and apply modelling approaches to address these challenges, improve the efficiency of closed-loop logistics processes, and increase the competitiveness with virgin materials and linear supply chains.