I. Introduction
Product-Service Systems (PSS) expand the traditional functionality of a product by additional services. Customers do not mandatorily possess the product, they pay for functionality. The focus is on the usage of the product. PSS rises attractive opportunities for the stakeholders. For instance, customers can profit from added value at cheaper prices and companies can benefit from long-term customer relations. Additionally PSS can lower the environmental impact because of long-term product lifecycles [1].