Bureaucrats are human beings, products of a democratic culture, and tied to professional and public service ethics. Bureaucratic units and subunits have their own unique missions and their own political and organizational histories that may resist external checks, particularly those imposed by special interest groups. Bureaucrats realize knowledge should play a dominant role in policy formulation, but they also concede some role to the political reaction that policies will generate. Because bureaucrats are people, they acquire perspectives and values that influence every aspect of their lives. Personal influences, however, are less important than knowledge and acceptance of politics in the bureaucratic process. Presidential bureaucratic influence is felt through personnel selection, legislation, government structure, and the budget. Congressional bureaucratic influence results from legislative and investigative oversight functions, personnel selection and staffing, and the budget. The public, especially professional associations and individual policy experts, exercises a great deal of influence over the Federal bureaucracy. The legal system offers an additional avenue for influence over bureaucratic policymaking, by defining rules about how decisions are made and by providing a legal process in which Federal agencies may be called to defend their decisions. 82 references.