The assumption that competition law and consumer protection are mutually reinforcing is rarely challenged. The theory seems uncontroversial. However, because a positive interaction between the two is presumed to be self-evident, the frequent conflicts that do in fact arise are often dealt with on an ad hoc basis, with no overarching legal authority. There is a clear need for a detailed and coherent understanding of exactly where the complements and tensions between the two policy areas exist. Dr Cseres in-depth analysis provides that understanding. Proceeding from the dual perspective of law and economics that is, of justice, fairness, and reasonableness on the one hand, and of efficiency of the other she fully considers such underlying issues as the following: the role of competition law and consumer law in a free market economy; the notion of consumer welfare; the effect of the modernisation of EC competition law for consumers; etc.