Based on a longitudinal case study of four interorganizational product development collaborations, this paper identifies a lure to cross-functional integration that has hereto been neglected. In particular, findings suggest that when the buyer firm separates the Research and Development (R&D) Department from the Procurement Department, the two departments play a good cop–bad cop strategy toward the supplier. Thereby, they are able to foster a high level of goodwill trust between R&D personnel of the collaborating firms, while procurement personnel maintain a high level of formal control. Using an intricate sample design with polar cases, the study shows that cross-functional integration of the two departments hampers interorganizational goodwill trust at the benefit of formal control. The findings offer a way forward for managers seeking to reap the benefits of collaboration, while limiting their exposure to the associated risks.