We examine an export game where two firms (home and foreign), located in two different countries, produce vertically differentiated products. The foreign firm is the most efficient in terms of R&D costs of quality development and the foreign country is relatively larger and endowed with a relatively higher income. The unique (risk-dominant) Nash equilibrium involves intra-industry trade and the foreign producer manufactures a good of higher quality than the domestic firm. For low enough transport costs, this equilibrium is characterized by unilateral dumping; otherwise, reciprocal dumping emerges. We show that the implementation of antidumping (AD) policy can change significantly the nature of the game and give rise to various new Nash equilibria. For some parameters, an AD policy leads to a quality reversal in the international market whereby the low-quality firm becomes leader. We show that such a policy is desirable for the implementing country, though world welfare decreases. The paper also establishes an equivalence result between a price undertaking and an anti-dumping duty.JEL Classification: F12, F13