It is possible to distinguish in the federal administrative agencies, collectively known as “the bureaucracy,” a separate branch of government distinct alike from the executive and from the legislature. It is equally possible to argue that the administrative agencies, because they are the organs through which the law becomes effective and because they are at least nominally under presidential control, are parts of the executive establishment; or that through congressional control over appropriations they are extensions of the legislature. To the extent that the bureaucracy does in fact share all of these characteristics, it becomes the instrument through which the close fusion of executive and legislative functions required by the complex nature of modern government may be brought about under a constitution committed to the eighteenth-century doctrine of separation of powers.