Abstract : Research & Development (R & D) strategies in companies today try to move towards improving the productivity of the development process of mechanical products. The involvement of business actors, in all phases of development, is critical to maintain competitiveness factors. This finding is consistent with the recent strategy for product life cycle management (PLM). It provides integrated management of all the information and processes related to it, on its entire life cycle, in a context of extended enterprise. Approaches like "integrated" and "concurrent" engineering, have emerged at the crossroads of traditional design approaches like routine and innovative design. This has enabled the integration of downstream constraints at the earliest in the development process. This thesis is in the areas of integrated design and information management techniques, particularly focusing on the product-process couple. This involves the establishment of a methodology called Fabrication Based On Knowledge (FabK) to assist product development, with Knowledge Based Engineering (KBE) applications, in a process-oriented design for manufacturing (DFM). In order to validate our proposed methodology, we carried out our experimentations within an automotive company, on products such as a vehicle's air ducts, and manufacturing processes such as plastic welding.