This document contains temporary Income Tax Regulations relating to U.S. taxpayers operating, investing or otherwise conducting business in the currencies of certain European countries that are replacing their national currencies with a single, multinational currency called the euro. These regulations provide rules relating to adjustments required for qualified business units operating in such currencies and rules relating to the tax effect of holding such currencies or financial instruments or contracts denominated in such currencies. The text of these temporary regulations also serves as the text of proposed regulations published elsewhere in this issue of the Federal Register.