Applied Research Associates Inc., Albuquerque, New Mexico (HDTRA124D0002); Booz Allen Hamilton Inc., McLean, Virginia (HDTRA124D0003); Leidos Inc., Reston, Virginia (HDTRA124D0004); Peraton Inc., Herndon, Virginia (HDTRA124D0005); SRC Inc., North Syracuse, New York (HDTRA124D0006); Two Six Labs LLC (doing business as Two Six Technologies), Arlington, Virginia (HDTRA124D0007); Leidos Inc., Reston, Virginia (HDTRA124D0008); Noblis Inc., Reston Virginia (HDTRA124D0009); Parsons Government Services Inc., Centreville, Virginia (HDTRA124D0010); and Signalscape Inc.,* Cary, North Carolina (HDTRA124D0011), were awarded a multiple award, indefinite-delivery/indefinite-quantity contract with a maximum cumulative ceiling of $4,000,000,000 for the Defense Threat Reduction Agency’s (DTRA) Research and Development Directorate. This contract provides for performing research, development, test and evaluation, procurement, maintenance, support, systems engineering and/or sustainment to provide scientific and technological solutions to meet the Department of Defense’s priority Combating Weapons of Mass Destruction objectives. Work under this program is divided into three pools: artificial intelligence, machine learning, data science, and software development (Pool 1); operations and countermeasures in a chemical, biological, radiological, and nuclear environment (Pool 2); and targeting, information operations and irregular warfare (Pool 3). The maximum ceiling value applies to all awards issued under all three pools. Fiscal 2024 research, development, test and evaluation funding in the amount of $500,000 ($50,000 minimum guarantee per contract) will be obligated at the time of award and will expire at the end of fiscal 2025. All other funding will be obligated as task orders are issued using research, development, test and evaluation; operations and maintenance; procurement; and other funding. Work locations will be determined at the task order level. The contract will include a five-year base ordering period and a five-year optional ordering period. The ordering period will go through May 2029; if all options are exercised, the ordering period will go through May 2034. This award is the result of a full and open competitive acquisition. Proposals were solicited through SAM.gov and 27 offers were received. DTRA, Fort Belvoir, Virginia, is the contracting activity.