This new Transnational Law casebook introduces the international legal order as it presents itself at the beginning of the 21st century. The book’s goal is to orient students in transactions and disputes reaching beyond national boundaries. It offers them the basic knowledge and understanding of transnational law that every lawyer should possess today, and it lays the foundations upon which more specialized courses can build. The book is divided into five categories: the respective Actors, the nature of their Interaction, the major forms and effects of transnational Law, transnational mechanisms of Dispute Resolution, and the Domestic Effects of international rules. It approaches the material from an evolutionary perspective and shows how the landscape with regard to each of the five topics has changed, especially over the last half-century.