The Federal Acquisition Regulation (FAR) is the principal set of rules in the Federal Acquisition Regulations System.[1] The FAR System governs the “acquisition process” by which executive agencies of the United States federal government acquire (i.e., purchase or lease) goods and services by contract with appropriated funds.[1][2][3] The process consists of three phases:[4] Need recognition and acquisition planning; Contract formation; and Contract administration.
The FAR System regulates the activities of government personnel in carrying out that process. The FAR System is codified at Title 48, Chapter 1 of the Code of Federal Regulations. These requirements can be found in the Code of Federal Regulations at 48 C.F.R. 31.
While nearly all federal government executive agencies are required to comply with the FAR, some executive agencies are exempt (e.g., the Federal Aviation Administration[5][6] and the U.S. Mint[7][8]). In those cases, the agency promulgates its own specific procurement rules.[9][10] The remainder of the FAR System consists mostly of sets of regulations issued by executive agencies of the federal government of the United States to supplement the FAR.[1]
The purpose of the FAR is to provide “uniform policies and procedures for acquisition.”[11] Among its guiding principles is to have an acquisition system that satisfies customer’s needs in terms of cost, quality, and timeliness; minimize administrative operating costs; conduct business with integrity, fairness, and openness; and fulfill other public policy objectives.[12]
Further reading
https://en.wikipedia.org/wiki/Federal_Acquisition_Regulation