This course will serve as an introduction to the U.S. federal tax aspects of the cross-border flow of capital and labor. At the most basic level, we will explore the distinction, both for income and for estate and gift tax purposes, between a U.S. and a foreign person. We will then compare and contrast the manner in which U.S. and foreign persons (including tax expatriates) are subject to income tax. We will also cover the special tax regimes applicable to investments made by U.S. persons in foreign corporations (i.e., the controlled foreign corporation and passive foreign investment company regimes) as well as an introduction to the foreign tax credit rules. Throughout the course of the semester we will consider the potential impact of tax treaties on the rules in the Internal Revenue Code.