Abstract: One of the main inroads to the so-called Classic Contract Law has been made by implied terms imposing a certain quality on the subject matter of contracts, an outcome that has been achieved by resorting to a variety of legal sources and tools. Modernization and harmonization of European Contract Law, to this respect, has mainly focused on sales contracts (as an archetype to others), including the requirement of conformity in its terms. The article deals with the concept of conformity and assesses its profound implications to traditional notions of Contract Law. As in many European legal systems the principle of conformity is restricted to certain types of sales, it is necessary to furtherly deepen in national Law to assess the existence of equivalent requirements to conformity whenever it does not apply. To this end, the work undertakes a Comparative Law perspective following a realistic and functional methodology. As a central instrument in the modernization of Contract Law, the article assesses the desirability of generalizing the principle of conformity to all contracts, a position that, from a legal and economic perspective, is not recommended. The relationship between freedom of contract and reasonable expectations of the parties is an underlying tension to this matter in respect of which the present work proposes a solution.
European Review of Private Law