Since its founding in 1982, the Small Business Innovation Research (SBIR) program has become the largest and most comprehensive public research and development funding program of small business research in the United States. An underlying tenet of the SBIR program, and the related Small Business Technology Transfer (STTR) program, is that small and young firms are an important source of new ideas that provide the underlying basis for technological innovation, productivity increases, and subsequent economic growth. By involving qualified small businesses in the nation's research and development efforts, SBIR/STTR grants stimulate the development of innovative technologies and help federal agencies achieve their missions and objectives. At the request of the Department of Energy (DOE), this report examines the SBIR and STTR programs at DOE, focusing on the effectiveness of DOE's SBIR/STTR processes and procedures on topic and awardee selection; DOE outreach efforts to SBIR and STTR applicants; collaborations created between small businesses and research institutions on account of the programs; a range of direct economic and non-economic impacts to awardees; and the role of SBIR/STTR programs in stimulating technological innovation and contributing to DOE's research and development needs, whether directly from awardees or indirectly through spillovers from other firms.