This text provides a comprehensive guide to the principles of European contract law. They have been drawn up by an independent body of experts from each Member State of the EU, under a project supported by the European Commission and many other organizations. The principles are stated in the form of articles, with a detailed commentary explaining the purpose and operation of each article and its relation to the remainder. Each article also has extensive comparative notes surveying the national laws and other international provisions on the topic. "The Principles of European Contract Law Parts I & II" cover the core rules of contract: formation, authority of agents, validity, interpretation, contents, performance, non-performance and remedies. The articles previously published in Part I (1995) are included in a revised and re-ordered form. Throughout Europe there is great interest in developing a common European legal culture. The European Parliament has twice called for the creation of a European Civil Code. The principles of European contract law are essential steps in these projects.