Government in the Sunshine Act in the context of Title 5 of the United States Code

Legislative definitions of an agency of the federal government of the United States are varied, and even contradictory. The official United States Government Manual offers no definition. While the Administrative Procedure Act definition of "agency" applies to most executive branch agencies, Congress may define an agency however it chooses in enabling legislation, and through subsequent litigation often involving the Freedom of Information Act and the Government in the Sunshine Act. These further cloud attempts to enumerate a list of agencies.

The executive branch of the federal government includes the Executive Office of the President and the United States federal executive departments (whose secretaries belong to the Cabinet). Employees of the majority of these agencies are considered civil servants.