Book excerpt: The tax rules of the United States and other countries have intended and unintended effects on the operations of multinational corporations, influencing everything from the formation and allocation of capital to competitive strategies. The growing importance of international business has led economists to reconsider whether current systems of taxing international income are viable in a world of significant capital market integration and global commercial competition. In an attempt to quantify the effect of tax policy on international investment choices, this volume presents in-depth analyses of the interaction of international tax rules and the investment decisions of multinational enterprises. Ten papers assess the role played by multinational firms and their investment in the U.S. economy and the design of international tax rules for multinational investment; analyze channels through which international tax rules affect the costs of international business activities; and examine ways in which international tax rules affect financing decisions of multinational firms. As a group, the papers demonstrate that international tax rules have significant effects on firms' investment and other financing decisions.