The Kyoto Protocol was negotiated by more than 160 nations in December 1997.Their objectives is to reduce net emissions of certain greenhouse gasses, primarily carbon dioxide.They agreed to limit their greenhouse gas emissions, relative to the levels emmitted in 1990. Each of the participating developed countries must decide to meet its respective reduction goal during a five-year period (2008-2012). This convention was commenced on December 1st to the 11th, 1997. The United States agreed to reduce emissions from 1990 levels by 7 percent during the period 2008 to 2012.
Here are some sites about the Kyoto Protocol: