If this were a book about some long-established, traditional, or otherwise well-defined area of law—a common law field such as contracts, say, or a regulatory area like environmental law—there would be no call for the editor to define the subject matter, or to seek to justify it. To offer a book on electronic commerce law, however, is to invite the questions: Does such a field of law actually exist? What justification is there for treating this field as a coherent body of law? We must first understand what electronic commerce is. Although different definitions of the term may be appropriate in different contexts,1 for purposes of this book electronic commerce consists of commercial activity that is accomplished with some substantial involvement of the Internet. The inception of electronic commerce may be dated to 1995, when the U.S. National Science Foundation privatized its internetworking project, the NSFNet, eliminating the acceptable use policy that had restricted the network’s use to noncommercial purposes. It was in that year that Amazon.com, craigslist, and eBay got their start. The early, influential judicial decisions dealing with ecommerce issues began arriving in the mid-1990s—or a bit earlier, if we expand the scope to include legal issues arising from the use of proprietary online services like America Online, CompuServe, and Prodigy. In contracting, for example, ProCD v. Zeidenberg2 validated the procedure of money-now, terms-later contracts, which paved the way for online clickwrap contracts.