A free trade agreement is a pact between two or more countries to eliminate tariff and nontariff barriers affecting trade among themselves, while each participating country applies its own independent schedule of tariffs to imports from countries that are not members. 

The United States has completed or is in the process of negotiating free trade agreements with several countries and regions.

Opening Markets for Growth: The U.S. FTA Agenda (2006; .pdf)

Gains From Recent FTAs (2006; .pdf)

Country Free Trade Agreements and Negotiations

Regional Free Trade Agreements and Negotiations