Modern antitrust law is global antitrust law. Markets are becoming increasingly global, or at least multinational. Mergers between large corporations must typically get approval in both the United States and in the EU, for their activities often affect both markets. Cartels in one nation affect supply in others, and countries are increasingly entering into treaties with each other about the content or enforcement of competition laws. Thus, businesspeople, lawyers, and law-makers can no longer content themselves with understanding only the antitrust and competition law of their home country. Modern antitrust law also differs from traditional antitrust law in that it now reflects the dominance of the economic model of analyzing antitrust and competition policy. Against this background, this new casebook represents the first comprehensive effort to examine US and EC competition law cases and decisions within a common analytical framework strongly based on economic theory. It is an innovative casebook addressed to all students, not only from the US and Europe, but also from all jurisdictions having competition laws, providing insights into the two major global antitrust regimes in the world.