Sorting out the appropriate roles of each level of government in addressing climate change is far more complicated than the specific question of whether State climate change programs should be preempted. This Paper raises more comprehensive and complex questions that the Committee must consider: what roles are best played by each level of government as we marshal our country's resources to address climate change and how should these roles be reflected in Federal legislation. Many State and local governments have begun to address climate change, as the Subcommittee heard last year in testimony from State and local witnesses.2 Activity by State and local governments has helped reduce greenhouse gas emissions, has helped build a consensus that we need to address climate change nationally, and is helping to develop and test different policies. The country is now at the difficult and familiar stage of transitioning from multiple, often unconnected, State and local climate change programs to a comprehensive, national approach to addressing the global problem of climate change. For a variety of reasons, State and local environmental programs have often led to enactment of Federal environmental legislation.