The international nature of economic activity runs parallel with the international nature of restraints on competition. Cartel agreements, mergers, and even unilateral measures, such as calling for a boycott, can have effects that cross national borders. In contrast, the actual enforcement of an individual state’s laws is confined to that state’s territory. Due to this divergence, loopholes have arisen in the endeavors to combat restraints on competition. In principle, there are two possible approaches to finding a solution to this problem. One is international, the other national. Each includes a number of variations.