Brookhaven Science Associates (BSA) was established for the sole purpose of managing and operating Brookhaven National Laboratory (BNL) for DOE's Office of Science. BSA, a limited-liability company, was formed as a 50-50 partnership between Battelle, a nonprofit, applied science and technology organization, and The Research Foundation of State University of New York (SUNY) on behalf of Stony Brook University (SBU), the largest academic user of Laboratory facilities. BSA is the legal entity responsible for leading BNL successfully through the 21st century.

As of September 7, 2010, BSA entered into a partnership agreement with BNL and the DOE's Brookhaven Site Office concerning shared mission, values, and responsibilities. One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven also builds and operates major scientific facilities available to university, industry, and government researchers.

Both SBU and Battelle are strongly motivated to ensure Brookhaven's success. Being Brookhaven's closest university neighbor, SBU is the single largest user of BNL facilities; BNL facilities and scientific staff are essential to the vitality of the university's intellectual life and to the impact of many of its research programs. This expanding relationship includes joint appointments, joint initiatives, and SBU-BNL research endeavors.

A presence at Brookhaven enables Battelle to continue and advance its founding purpose "science in service to humanity," and to enhance the research partnership between Battelle and Brookhaven in major programs ranging from global climate research to nanoscience.