Article dans une revue: Corporate organization varies within countries and between countries. We develop a theory which explains the variation in levels of decentralization across firms and links it to the trade environment that firms face. We introduce firms with internal hierarchies in a Melitz and Ottaviano (2008) model of international trade. We show that international trade increases the conflict of interest between CEO/owners and middle managers within firms and these eventually lead to decentralized corporate hierarchies. We test the theory with original data on the internal organizations of 2200 Austrian and German firms and find that the empirical evidence is consistent with the model's predictions.