Integration of equipment suppliers in the design of the production system has often been associated with major benefits. However, from a managerial perspective, integration between the user and the suppliers of the production equipment is still challenging. Therefore, the purpose of the research is to explore how manufacturing companies can facilitate and manage equipment supplier integration when designing the production system. Based on an real time case study in the automotive industry 10 critical factors for successful supplier/user integration are identified, which can be classified into three categories: human factors, project management factors and design factors.