The European Commission recently published a study commissioned from Oxera on methods for quantifying damages for breach of competition law. The object is to try to find economic models which can, as closely as possible, determine the real value of damage to those affected by a breach. This calculation requires the identification of the ‘counterfactual situation’, in other words, an assessment of what would have happened if the infringement had not taken place. Then, it is necessary to consider what actually happened and convert the difference into a final damage value. The study examines in particular, the harm arising from ‘hardcore’ cartels (e.g. price fixing and/or market sharing by competitors) and ‘exclusionary conduct’ where dominant companies have restricted smaller players from entering the market or have limited their ability to compete. The report is intended to assist the Commission in developing guidance and to assist the national courts in making such calculations.