Executive orders, presidential memoranda, and proclamations are used extensively by Presidents to achieve policy goals, set uniform standards for managing the executive branch, or outline a policy view intended to influence the behavior of private citizens. The U.S. Constitution does not define these presidential instruments and does not explicitly vest the President with the authority to issue them. Nonetheless, such orders are accepted as an inherent aspect of presidential power. Moreover, if they are based on appropriate authority, they have the force and effect of law. This report discusses the nature of these written instruments, executive orders in particular, with a focus on the scope of presidential authority to execute such instruments, as well as judicial and congressional responses to their issuance.