This paper proposes and empirically investigates two strategies that companies can employ to involve indirect suppliers in new product development (NPD): supply network delegation; and supply network intervention. The implications of the two strategies are explored. The paper brings together the traditional NPD literature, organizational behaviour and organizational economics literature, and reports on three in-depth case studies of NPD projects, involving 39 semi-structured interviews across three supply networks. The findings reveal different manifestations of the two strategies of supply network intervention and delegation, when applied as part of supplier involvement in product development, and positive and negative indications of deleg...