Supplier involvement in NPD projects: the buyer's perspective on the complementary roles of social capital and social exchange for project performance

Purpose Buying firms involve suppliers early in New Product Development (NPD) projects to benefit from their capabilities. The authors investigate the joint impact on project performance improvement, of the social capital established throughout the project, and the strategic preferred buyer/supplier statuses awarded prior to the project, from the buyer's perspective. Design/methodology/approach The authors propose a conceptual model underlining the complementary contribution to project performance of social capital dimensions and of preferred partners' statuses resulting from social exchange expectations. The model is analyzed with Partial Least Squares using 80 responses of purchasers and R&D managers involved in collaborative NPD projects with suppliers. Findings The relational capital built during the project has a positive central role, with a direct impact on NPD project performance and mediating effects through cognitive and structural capitals. The preferred partners' statuses have strong direct impacts on performance, and mediating effects that do not completely supplant the social capital's contribution. Practical implications The implications for the efficient management of supplier involvement are twofold. First, the authors encourage strategic investments of buying firms to acquire preferred buyer's status and to support preferred supplier programs. Second, the authors alert them on the importance of establishing trust and shared cognition during the project. Originality/value This study captures NPD project performance from the social angle of buyer–supplier relationship management. It demonstrates the complementarity of relationship management at the strategic and operational levels, before and during the project unfolding.