Crossing boundaries: Involving external parties in innovation

To improve the return on investments in innovation, firms increasingly open up their new product development (NPD) processes by inviting external parties to participate. This dissertation focuses on the involvement of three different types of external parties in the NPD process: suppliers, customers, and the ‘crowd’. In the second chapter, a meta-analysis of the extant literature on supplier and customer involvement in NPD is presented. It investigates the antecedents and consequences of supplier and customer involvement in NPD. The third chapter focuses on customer participation in outsourced NPD. It shows how multiplex relationships that can cause role synergy, role conflict, and role ambiguity, moderate the effect of customer participation on the task performance of the developing firm. The fourth chapter deals with online idea generation contests in which ideas are crowdsourced in competitive settings. It provides insights into the prize structure that best stimulates the crowd to deliver creative ideas. Collectively, the research presented in this dissertation sheds light on how to successfully manage the participation of external parties in NPD, a timely managerial issue