Prior research into the effects of cultural differences between MNE home and host countries on expatriate staffing decisions in foreign subsidiaries has produced a large number of conflicting findings. We address some of these conflicting findings and aim to advance theory in two ways. First, we draw on transaction cost economics to explain why and how the effects of cultural distance on the proportion of expatriate parent-country nationals form a curvilinear instead of a linear relationship, as commonly proposed. Second, we integrate the values-based cultural distance concept with the norms-based tightness-looseness concept. This allows us to simultaneously account for cultural differences between countries and location-bound normative cultural effects within countries, which cannot be overcome solely through expatriate learning and adaptation. Using a large global dataset of Japanese MNEs, we find support for a convex relationship between cultural distance and the proportion of expatriate parent-country nationals. We also find a moderating (steepening) effect of tightness-looseness on this relationship. The results reconcile some of the tensions between the subjectivists' values-based approach, which positions culture in the shared cognitions realm, and the structuralists' approach, which places culture in a normative situational environment.