This paper examines two policy instruments: privatization of the domestic publicfirm and imposition of a tariff on foreign private firms in an international mixedoligopolistic model with asymmetric costs. It first demonstrates that different ordersof moves of firms will imply different government decisions on optimal tariff and onprivatization policy. Following Hamilton and Slutsky (1990), this paper then uses anextended game to discuss endogenous roles. It indicates that the efficiency gain thathighlights the importance of foreign competition is crucial in determining thewelfare-improving privatization policy. Moreover, the endogenous equilibria areassociated with different government decisions on privatization.