Obsidian Solutions Group LLC, Fredericksburg, Virginia (HDTRA122D0008); Veteran’s First LLC, Fairfax, Virginia (HDTRA122D0009); and RMGS Inc., Virginia Beach, Virginia (HDTRA122D0010), are being awarded an indefinite-delivery/indefinite-quantity, multiple award contract for assessments, exercises, and modeling and simulation support (AEMSS). The maximum dollar ceiling including the base period and option period for all three contracts combined is $850,000,000. Work will be performed at various locations throughout the world. Task orders issued under the contract may be for a duration of one year past the last ordering date of the contracts. Funding will be obligated for each task order and no funds are obligated on the basic contracts. The contracts were competitively procured via solicitation HDTRA120R0076 and the government received 18 offers. The Defense Threat Reduction Agency, Nuclear Enterprise Contracting Office, Fort Belvoir, Virginia, is the contracting activity.