Cross-border trade substantially fosters the wealth of nations. Today it is a multi-tril- lion euros business. Cross-border dealings are in particularly dependent on reliable rules and legal certainty. Legal ramifications and a dependable legal framework are thus of the absolute essence. Commercial law is the branch of the law called upon to perform this task. In a cross-border, and that is: in a truly international context, this poses a particular challenge. Not surprisingly, international commercial law has become the main field of international legal unification. The commercial needs involved are all too pressing and too real to be ignored or neglected. The United Nations Convention on Contracts for the International Sale of Goods (CISG) is said to be the greatest success of substantive uni- form law. The law of carriage of goods or passengers comes a close second if not an equal-ranked first. Beneath and besides this unification of law between States another level of 'private codifications' has developed over the last decades. Its most prominent protagonists are the Incoterms, the Uniform Customs and Practices for Documentary Letters of Credit (UCP) and the UNIDROIT Principles on International Commercial Contracts (PICC). The ensuing panorama is both complex and fascinating. Its fascina- tion also stems from the manifold interfaces and interactions between the various sub- branches of commercial law.