This is a definitive contract awarded by the Headquarters of a civilian federal agency (ID 6900|6920|VPFAAHQ-A) to Parsons Government Services Inc., a subsidiary of Parsons Corporation. The contract has a cost plus award fee pricing type and a ceiling value of $1,886,466,998.12. The contractor must furnish professional, technical, and support labor, material, supplies, management services, data, and facilities required to accomplish the work to be ordered under the contract. The contract has no set-aside designation. Parsons is a leading provider of services such as engineering, construction, program management, environmental remediation, cybersecurity, and software development to various federal agencies. The contract supports the agency's diverse mission requirements and allows for the rapid acquisition of Parsons' services through multiple Indefinite Delivery Vehicles, including the $869 million Scientific, Technical, Engineering and Program Support Services (STEPSS) contract for the Army and the $850 million Assessment, Exercise, and Modeling and Simulation Support (AEMSS) contract with the Defense Threat Reduction Agency.