Executive orders requiring agencies to impose certain conditions on federal contractors as terms of their contracts have raised questions about presidential authority to issue such orders. These orders typically cite the President's constitutional authority, as well as his authority pursuant to the Federal Property and Administrative Services Act of 1949 (FPASA). FPASA authorizes the President to prescribe any policies or directives that he considers necessary to promote "economy" or "efficiency" in federal procurement. For example, there have been legal challenges to orders (1) encouraging agencies to require the use of project labor agreements on large-scale construction projects; (2) requiring that certain contracts include provisions obligating contractors to post notices informing employees of their rights not to be required "to join a union or to pay mandatory dues for costs unrelated to representational activities"; and (3) directing departments and agencies to require their contractors to use E-Verify to check the work authorization of their employees. These challenges have alleged, among other things, that the orders were beyond the President's authority, under FPASA or otherwise. A 2011 draft executive order that would have directed departments to require contractors to "disclose certain political contributions and expenditures" raised similar and additional questions as to whether it would have been within the President's authority, as it resembled legislation that was considered, but not enacted, by the 111 th Congress. The issuance of executive orders requiring agencies to impose certain conditions on federal contractors and subcontractors has practical as well as legal significance given the scope of federal procurement activities. Spending on federal contracts totaled $541.1 billion, or approximately four percent of U.S. gross domestic product, in FY2010, and approximately 22% of U.S. workers are employed by entities subject to requirements placed on certain federal and federally funded contractors and subcontractors pursuant to executive orders. Thus, some commentators have expressed concern that, if presidential authority to issue directives imposing requirements on federal contractors is construed broadly, the executive branch effectively could regulate significant segments of the U.S. economy. This report provides background on the authorities under which Presidents have historically issued executive orders pertaining to federal contractors and the legal issues potentially raised by the exercise of these authorities. It also surveys key cases challenging executive orders pertaining to federal contractors, which typically were issued under the authority granted to the President under the FPASA. The report concludes by addressing potential limitations on and congressional responses to presidential exercises of authority regarding federal contractors. Broadly speaking, executive orders are directives issued by the President. Such directives may have the force and effect of law if they are based on express or implied constitutional or statutory authority. Executive orders are "generally directed to, and govern actions by, Government officials and agencies" and are sometimes characterized as "affect[ing] private individuals only indirectly." However, they can effectively reach private conduct, such as when an executive order requires agencies to incorporate particular terms in their contracts, or prohibits them from entering contracts with persons who do not comply with certain conditions. Presidents from Franklin D. Roosevelt through Barack Obama have issued orders that seek to leverage the government's procurement spending to promote socio-economic policies that some commentators would characterize as extraneous to contractors' provision of goods or services to the government. The issuance of such orders has been controversial, partly because of disputes regarding the desirability of the underlying socio-economic policies to be promoted through the procurement process and partly because some commentators characterize such presidential actions as trespassing upon congressional prerogatives. Presidential power to issue executive orders must derive from the Constitution or from an act of Congress. Contractor-related executive orders historically have been issued based upon the President's powers under Article II of the Constitution or the powers delegated to the President by FPASA. The earliest orders using the procurement process to further socio-economic policies of the President appear to have been issued during World War II, and were based upon the President's constitutional authority as commander-in-chief. Later, during the 1960s, several orders were issued under the authority of prior executive orders or other provisions of federal law. More recently, orders have been issued based on presidential authority under FPASA. FPASA states that its purpose is to "provide the Federal Government with an economical and efficient system for … [p]rocuring and supplying property and nonpersonal services" and authorizes the President to prescribe any "policies and directives" consistent with the act that he "considers necessary to carry out" the act's goals of efficiency and economy. Courts and commentators have disagreed as to whether Congress intended to delegate to the President broad authority over procurement or authority only over narrow "housekeeping" aspects of procurement, and FPASA's legislative history is arguably inconclusive. While a few courts have found that the President has "inherent authority" over procurement, questions have arisen about whether such authority survived the enactment of FPASA. Some commentators have suggested that the authority delegated to the President under FPASA is so broad that Presidents do not need to assert inherent authority over procurement. Parties challenging procurement-related executive orders and actions taken pursuant to such orders may raise different legal issues depending upon whether the President issues the executive order pursuant to the statutory authority granted to him by FPASA or under his constitutional authority. When the President relies upon the authority delegated by FPASA, courts may treat challenges alleging that presidential actions exceed statutory authority under FPASA as questions of statutory interpretation. Such courts have focused upon the text and legislative history of FPASA, as well as prior uses of presidential authority under FPASA, in determining whether Congress contemplated the President taking the challenged actions when it delegated authority to prescribe policies and procedures "necessary" to promote "economy" and "efficiency" in federal procurement. In a few cases, parties have unsuccessfully challenged a contractor-related executive order by asserting that FPASA itself, or a particular action taken under it, runs afoul of the nondelegation doctrine, which concerns the delegation of legislative power to the executive branch. The premise of the nondelegation doctrine is that Article I of the Constitution vests legislative power in Congress to make the laws that are necessary and proper, and "the legislative power of Congress cannot be delegated" to other branches of government. A congressional delegation of legislative authority will be sustained, according to the Supreme Court, whenever Congress provides an "intelligible principle" that executive branch officials must follow and against which their actions may be evaluated. Today, the nondelegation doctrine constitutes only a "shadowy limitation on congressional power," as the Court has not struck down a congressional delegation since 1935. Parties challenging contractor-related executive orders and/or courts reviewing such challenges have sometimes also articulated constitutional arguments based on the three-part scheme for analyzing the validity of presidential actions set forth in Justice Jackson's concurring opinion in Youngstown Sheet & Tube Company v. Sawyer . This analysis has appeared when presidential action has been taken pursuant to the President's express statutory authority under FPASA, when presidential action has been viewed as conflicting with an existing statute, and when presidential action has been based on the President's constitutional authority. In Youngstown , the Supreme Court struck down President Truman's executive order directing the seizure of the steel mills during the Korean War. It did so, in part, because the majority deemed the order to be an unconstitutional violation of the separation of powers doctrine given that it was, in essence, a legislative act, and no constitutional provision or statute authorized such presidential action. To the contrary, Congress had expressly rejected seizure as a means to settle labor disputes during consideration of the Taft-Hartley Act. The concurring opinion of Justice Jackson in Youngstown , which has come to be regarded as more influential than the majority opinion, set forth three types of circumstances in which presidential authority may be asserted and established a scheme for analyzing the validity of presidential actions in relation to constitutional and congressional authority. First, if the President has acted according to an express or implied grant of congressional authority, presidential "authority is at its maximum, for it includes all that he possesses in his own right plus all that Congress can delegate," and such action is "supported by the strongest of presumptions and the widest latitude of judicial interpretation." Second, in situations where Congress has neither granted nor denied authority to the President, the President acts in reliance only "upon his own independent powers, but there is a zone of twilight in which he and Congress may have concurrent authority, or in which its distribution is uncertain." Third, in instances where presidential action is "incompatible with the express or implied will of Congress," the power of the President is at its minimum, and any such action may be supported pursuant only to the President's "own constitutional powers minus any constitutional powers of Congress over the matter." In such circumstances, presidential actions must rest upon an exclusive power, and the courts can uphold the measure "only by disabling the Congress from acting upon the subject." Because Congress had passed three statutes on seizure of private property in particular circumstances and had considered, but not granted, the President general seizure authority for use in emergencies, Justice Jackson's taxonomy supported the majority's holding that the President lacked the authority to seize the steel mills in Youngstown . Some commentators have proposed that this taxonomy ought to serve to invalidate at least certain contractor-related executive orders. Such arguments are most common when the executive order requires agencies to impose requirements similar to those previously considered, but not passed by Congress. However, separation of powers arguments generally have been unavailing so long as the executive order is also based on authority delegated to the President under the FPASA. When acting under the FPASA, the President arguably is acting according to an express grant of congressional authority, and, under Youngstown 's first category, such actions are "supported by the strongest of presumptions and the widest latitude of judicial interpretation."