The U.S. Environmental Protection Agency’s cost-free, online ENERGY STAR tool, Portfolio Manager, is being used to measure energy performance in over 120,000 buildings across the U.S. The tool can help assess the whole energy use of existing buildings, allow energy performance comparison to a national average, track changes in energy and water use over time in single buildings, groups of buildings, or entire portfolios, and track greenhouse gas (GHG) emissions reductions and cost savings. It is available at www.energystar.gov/benchmark.