Efforts to reduce greenhouse gas emissions have advanced at the national level through Congress and the EPA, and at state and regional levels as well.  Cap and Trade has been the approach favored in legislative vehicles in Congress.  The EPA, however, under the direction of the White House, has advanced its plans to regulate greenhouse gases under existing law, the Clean Air Act.  At the regional level, some governors have entered into agreements with nearby states to reduce greenhouse gases through cap and trade and low carbon fuel standards.  To find out more about each approach, visit the individual pages linked above.  To see what greenhouse gas related laws exist in your state, visit the  Institute for Energy Research's state pages.