How is this done?

US citizens & residents r taxed on their world-wide income. You must file a return if ur income exceeds the filing requirement for ur filing status. See IRS Pub 501 for filing requirement amounts.

You may be able to exempt some foreign earned income from US taxes, or alternatively u can take a credit for the foreign income taxes paid against ur US tax liability. You cannot do both but if you're eligible for both u can choose the method that results in the lowest tax for you. See IRS Pub 54 for more information.

If u work for a US employer, FICA & Medicare will be withheld from ur wages.

If u work for a non-US employer, u will pay the equivalent taxes of the country where u r working unless a tax treaty provides otherwise. Most of the time tax treaties get u credit in the US Social Security system while paying the foreign tax though. Google ''tax treaties'' on the IRS website for more information on that.

If u r self-employed, u pay the Self-Employment tax. This applies to working overseas as well as in the US.

go to irs.gov & type in ''totalization''--that will give u the list of countries with a social security agreement & a link to the SSA for the text of the agreement.

Note, the totalization agreements do two things. If a US employer sends u abroad for 5 years or less, u continue to pay into social security. If u r hired abroad or it is longer than 5 years, u pay into the other country is system, though both systems will consider time in the other system to increase the odds u qualify for payments somewhere.