The Cost Accounting Standards (CAS) are a set of 19 standards and rules promulgated by the U.S. government to be used in establishing costs on negotiated procurements. CAS differs from the Federal Acquisition Regulation (FAR) because the FAR applies to most contractors, while CAS applies primarily to the larger ones.
The Cost Accounting Standards Board (CASB) is a function located within the White House's Office of Federal Procurement Policy (OFPP). The OFPP is a component of the U.S. Office of Management and Budget (OMB), which, in turn, is the largest office within the Executive Office of the U.S. President. The OFPP provides overall direction for government-wide procurement procedures and promotes economy, efficiency, and effectiveness in the procurement process.