Product/Service-Systems (PSS) strategies are a part of an overall movement towards a service-based society that is increasingly knowledge and information based. Knowledge sharing for cross-company innovation and development projects has been recognized as troublesome, since disparate knowledge domains must be brought together in a cohesive way to support both creativity and innovations. Stage-Gate process models are widely used in collaborative development projects but they do not suggest how to assess the degree of understanding of the produced information and the results in projects. A successful assessment of knowledge should be used for designing the next development steps in form of work methods and tools. This paper describes an approach for supporting Knowledge Management and Knowledge Sharing in the development of PSS. Finally, a concept for supporting knowledge assessment is proposed, based on designing and visualizing knowledge paths.