In the multi-level legal order, it is not unusual for a legal relationship between private parties to be governed by multiple Union rules on, for instance, non-discrimination, free movement, competition and the internal market more broadly. Nor is it uncommon that, on the face of it, national private law creates rights and duties as well. In such situations of concurrence, the question that arises is whether the interested party may elect the rule of his choice. Is he entitled to choose the r...