Under economic globalization, anti-competitive acts transcend national borders and become a challenge for competition law as traditionally conceived. Most countries have been dealing with cross-border competition problems by using two basic methods: unilaterally extending national competition law's jurisdiction to acts conducted in foreign territory and cooperating in enforcing competition law. However, while the unilateral enforcement of competition law harms international comity, international cooperation in this area is constrained by conflicting national interests. Against the backdrop of such limits of statist mechanisms, this chapter examines the role of multi-national corporations in the enforcement of national competition law at a transnational level. It argues that when a multi-national corporation internalizes competition laws of countries as standards for its behaviors, the corporation can provide a mechanism to project those national laws at the transnational level by exercising its private power in a socially responsible way.