This paper discusses the process of designing materials supply systems in product development projects. In the literature, the importance of success in new product development projects is stated. The structuring of new product development processes into some form of stage-gate process is advocated by many researchers and also widely used by companies. Much literature also states the necessity of shortening the time between concept and market for new products and highlights the need for working with overlapping activities in product development projects. The result presented in this paper is a structuring of the materials supply systems design process according to a stage-gate process. The structure was developed in close cooperation with a company within the automotive industry. The structure formalises the materials supply systems design process and facilitates the integration of materials supply aspects early on in product development projects. The materials supply systems design process is based on a general design method in order to further secure the quality of the design process.