In many corporate procurement processes all over the world, buyers face similar challenges. Procurement is typically repeated; switching from an incumbent to an entrant causes opportunity costs; the size of these costs can be affected by non-contracti relationship-specific investments; and there is little long-term commitment power. Despite these similarities, negotiating cultures differ strongly across the world. In some regions exerting competitive pressure seems to be the overriding objective. In other regions the buyer seems to protect the incumbent from direct competitive pressure. In order to gain a better understanding of the role of the negotiating culture in procurement processes, we compare a stylized competitive culture with a stylized protective culture. In particular, we investigate how the negotiating culture affects investment incentives, favoritism in the allocation of procurement contracts, and buyer profit