A trade agreement involving Canada, Mexico and the United States, implemented on January 1, 1994, with a 15-year transition period. The major agricultural provisions of NAFTA include: 1) the elimination of nontariff barriers - immediately upon implementation, generally through their conversion to tariff-rate quotas or ordinary quotas; 2) elimination of tariffs - many immediately, most within 10 years, and some sensitive products gradually over 15 years; 3) special safeguard provision; and 4) country-of-origin rules to ensure that Mexico does not serve as a platform for exports from third countries to the U.S.