The article traces the evolution of the judiciary's role as co-equal branch of government and as reviewer of legislative action, arguing that unlike foreign courts, the U.S. Federal courts are engaged in the political process. The judiciary's power over the years has included creating a system of Federal private law; joining with Congress and Federal agencies in administering regulations; defining property and privacy rights; and ordering social remedies validated by statutes and the Constitution. The most significant dimension of Federal judicial power is its ability to declare Acts of Congress and State legislatures unconstitutional. The article concludes that judicial activism was intended by the framers of the Constitution. 79 footnotes.