IRS PUBLICATION 54

A document that explains special tax rules for US citizens and resident aliens who work abroad or have income earned in a foreign country. Normally, income earned abroad is taxable, and citizens or resident aliens who earn income abroad are subject to the same filing requirements that is applicable to individuals living in America. Published by the Internal Revenue Service (IRS), it outlines the process of determining if a tax return should be filed, reporting earnings if paid in a foreign country (it requires reporting in US dollars), if estimated taxes should be settled, and filing the return itself. It also contains information on treating contributions to foreign organizations and taking foreign taxes into account.