; (2) to refrain from providing a product or service if the product or service can be procured more economically from a commercial source; and (3) to utilize Federal employees to perform inherently governmental functions (as that term is defined in section 5 of the Federal Activities Inventory Reform Act of 1998 ( Public Law 105–270 ; 112 Stat. 2384)). (b) General rule Except as provided in subsection (c) and notwithstanding any other provision of law, each agency shall obtain all goods and services necessary for or beneficial to the accomplishment of its authorized functions by procurement from private sources. (c) Exemptions Subsection (b) shall not apply to an agency with respect to goods or services if— (1) the goods or services are required by law to be produced or performed, respectively, by the agency; or (2) the head of the agency determines and certifies to Congress in accordance with regulations promulgated by the Director of the Office of Management and Budget that— (A) Federal Government production, manufacture, or provision of a good or service is necessary for the national defense or homeland security; (B) a good or service is so critical to the mission of the agency or so inherently governmental in nature that it is in the public interest to require production or performance, respectively, by Government employees; or (C) there is no private source capable of providing the good or service. (d) Method of procurement The provision of goods and services not exempt by subsection (c)(1) or (c)(2) shall be performed by an entity in the private sector through— (1) the divestiture of Federal involvement in the provision of a good or service; (2) the award of a contract to an entity in the private sector, using competitive procedures, as defined in section 152 of title 41, United States Code, and section 2302 of title 10, United States Code