Double taxation

Most countries impose taxes on income earned or gains realized within that country regardless of the country of residence of the person or firm. Most countries have entered into bilateral double taxation treaties with many other countries to avoid taxing nonresidents twice—once where the income is earned and again in the country of residence (and perhaps, for U.S. citizens, taxed yet again in the country of citizenship)—however, there are relatively few double-taxation treaties with countries regarded as tax havens.[15] To avoid tax, it is usually not enough to simply move one's assets to a tax haven. One must also personally move to a tax haven (and, for U.S. citizens, renounce one's citizenship) to avoid tax.