International taxation is an area of increasing importance in a world in which cross-border capital flows exceed USD1 trillion per day. Today, almost any transaction over a certain dollar amount will involve an international component, and focusing solely on the U.S. domestic tax aspects is a luxury few tax lawyers can afford. In addition, the international tax rules are constantly changing as new areas of business develop (such as electronic commerce and derivatives) and an attempt is made to fit them into a framework that in its basic contours is now over 80 years old. This book is an effort to provide law teachers with a relatively simple, easy to use casebook to teach U.S. international taxation. The field is notoriously complex- more so, perhaps, than any other area of Federal tax law. Thus, the author has made a conscious effort to document only the essentials. Throughout, the focus is on how the details of the tax law fit into a broader structure, which is described in the introduction.