This study aims at highlighting the current knowledge, practices and effects of collaborative and concurrent new product development processes in the framework of the Portuguese plastic processing industry. By means of a case study approach, the conditioning factors affecting the strategic collaborations among firms are systemized. Mutual dependence, trust, and extensive information sharing were identified as prerequisites factors for a better buyer-supplier interdependence and involvement, as well as for the overall benefit of the supply chain. Moreover, collaborative and concurrent new product development processes ask for the use of cost management practices and advanced technical specifications (standards) which emerge as technical and management tools to achieve higher levels of efficiency and quality at the lower cost. Practices such as target and kaizen costing, value engineering, and design-to-cost, were perceived to play a remarkable positive effect on the internal/external organizational boundaries.