The Fusion Energy Sciences (FES) Program of the Office of Science (SC), U.S. Department of Energy (DOE), hereby announces its interest in receiving grant applications for collaborative research in fusion energy science as part of the DIII-D national research program. The mission of the DIII-D program is to establish the scientific basis for the optimization of the tokamak approach to fusion energy production. The primary means to accomplish this mission is research utilizing the DIII-D tokamak to develop the ultimate potential of the tokamak concept as a magnetic confinement system. The DIII-D program also involves foundational fusion energy science research to make progress on a broad front toward predictive understanding of fusion plasmas. The major strengths of the program are the highly flexible and well-diagnosed DIII-D tokamak and a large collaborative research team from the national and international fusion community. All applications will utilize the DIII-D National Fusion Facility at General Atomics in San Diego, California. This includes modeling proposals utilizing DIII-D data. All applicants (whether requesting support for individual researchers or groups of researchers) planning to submit applications for new or renewal support in Fiscal Year 2016 should submit applications in response to this Funding Opportunity Announcement (FOA). Applications that are not primarily focused on research using the DIII-D tokamak are outside the scope of this FOA and should not be submitted under it. Applications primarily consisting of simple requests for experimental run time on DIII-D are also outside the scope of this FOA and should not be submitted under it.