This chapter details some of the tax issues arising from ecommerce and the commercial provision of digital resources. It focuses particularly on the problems confronting tax administrators in dealing with operations in the cloud. The chapter first provides a nontechnical explanation of operating in the cloud, to help the reader appreciate the tax issues raised by those operations. With the benefit of that explanation, the chapter identifies some of the difficulties that must be confronted when older tax principles are applied to new technologies. These new technologies make it difficult to fit what businesses do now into conventional tax categories. What kind of benefit does a user of digital content and cloud resources receive from the provider: is it a service, a rental of software, a rental of space on a server? And where is the benefit provided? Is it where the customer is located or is it where the provider’s hardware is situated? And if the latter, how does the tax system deal with the reality that, in a cloud configuration, that location may be changing? When a transaction is effected over the Internet, which jurisdiction has the right (and power) to tax it? These questions are of great importance in applying local, federal, and foreign tax laws to operations both local and global. The chapter briefly reviews how local tax administrators have dealt with new technologies in the past (such as the sale of software for personal computers) to suggest that the determination of a proper approach to taxing those transactions is likely to evolve as judges and administrators gain a greater appreciation of the reality of new technologies. It examines some of the current attempts by tax administrators to deal with issues raised by ecommerce and points out some of the weaknesses in current solutions. The chapter also reviews approaches that have been taken by tax administrators in foreign countries to reflect the diversity of approaches that currently exist in the tax treatment of ecommerce and digital resources.