Competition policy is an integral and prominent part of economic policy-making in the European Union. The EU Treaty prescribes its member states to conduct economic policy in accordance with the principle of an open market economy with free competition. More precisely, the goal of EU competition policy is to defend and develop effective competition in the common market. Under its Commissioners van Miert, Monti, and most recently, Kroes, the EU Commission has stepped up its effort to pursue and achieve this goal. A number of so-called hard-core cartels, such as the notorious vitamin cartel led by Roche, have been detected, tried in violation of Article 81 of the Maastricht Accord, and punished with severe fines. Also, Microsoft was hit hard by the strong hand of the Commission, having been severely fined for exploiting a dominant market position.