When dealing with complex product models, efficient knowledge distribution is essential to obtain success. This chapter describes how product models can be applied to support the knowledge distribution. The change toward individualization will radically affect the knowledge application in relation to the product. Through the application of a mass customization strategy, companies have a unique opportunity to create increased customer satisfaction. In a customized production, knowledge and information have to be easily accessible since every product is a unique combination of information. If the dream of a customized alternative instead of a uniform mass-produced product shall become a reality, then the cross-organizational efficiency must be kept at a competitive level. This is the real challenge for mass customization. A radical restructuring of both the internal and the external knowledge management systems is needed. Management of variety and closer integration with suppliers is necessary when the companies are working in a network.