The book is structured into two parts. The first part contains five essays exploring the origin, the ambitions and the possible future role of the CESL and its rules on the contents and effects of contracts. The second part contains specific comments to each of the model rules on the contents and effects of contracts laid down in Chapter 7 CESL (Art. 66-78). Together, the essays and comments in this volume contribute to answering the question of whether and to what extent rules such as those laid down in Art. 66-78 CESL could improve or worsen the position of consumers and businesses in comparison to the correspondent provisions of national contract law. The volume adopts a comparative perspective focusing mainly, but not exclusively, on German and Dutch law.