The Solar Energy Technologies Program (SETP), in the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE), held a technical workshop on high penetration of photovoltaic (PV) systems into the distribution grid on February 24-25, 2009, in Ontario, CA. The purpose of the workshop was to convene experts and practitioners in the PV/grid integration field to reach agreements on several key topics, including: Identifying key technical issues and barriers associated with high PV penetration levels; Determining high-priority research, development, and demonstration (RD&D) activities for the near-term, mid-term, and long-term to address the identified issues and barriers; and Defining performance requirements for high-priority RD&D activities.