This independent study provides an analysis of the public health impacts of the Regional Greenhouse Gas Initiative (RGGI) over its first six years of implementation (2009 to 2014). RGGI is the nation’s first regional regulatory program designed to reduce greenhouse gas (GHG) emissions from large electric power plants, and builds from a long and successful tradition in the Northeast states of using market-based programs to cost-effectively reduce air pollution. Since RGGI started in 2009, the program has raised nearly $3 billion to support the RGGI states’ investments in energy efficiency, renewable generation, and other public benefit programs, and these states are on track to achieve reductions of GHG emissions of 45 percent below 2005 levels by 2020.