Description: This report focuses on energy use in buildings, which account for over one-third of all energy used in the United States. Significant energy savings in buildings are possible through the use of commercially available, cost-effective, energy efficient technologies; yet adoption rates for these technologies are often low. Interviews with industry, property managers, homeowners, and others were used to explore why technology adoption rates are so low. Past Federal efforts to encourage energy efficiency are reviewed, and policy options for encouraging the adoption of energy efficient technologies are discussed.