Potential Risks and Benefits of Gain-of-Function Research is the summary of a two-day public symposium on Gain of Function (GOF) research. Convened in December 2014 by the National Research Council and the Institute of Medicine, the main focus was to discuss principles important for, and key considerations in, the design of risk and benefit assessments of GOF research. Participants examined the underlying scientific and technical questions that are the source of current discussion and debate over GOF research involving pathogens with pandemic potential. This report is a record of the presentations and discussion of the meeting.