The U.S. Department of Energy (DOE), Office of Nuclear Energy (NE) and Office of Science (SC), are seeking an Expression of Interest (EOI) from universities, companies, or organizations who are interested in the Molten Salt Reactor Experiment (MSRE) secondary loop salt coolant for nuclear reactor applications. Such applications may support any stage of the reactor life cycle from concept through operations, and may include experiments, related testing, and/or direct use in a reactor. DOE is not currently preparing any requests for information, requests for proposals, or funding opportunity announcements related to this EOI.