This compendium of over 500 entries on the most important and relevant personalities, programs, activities, and agencies of U.S. intelligence, beginning with the Sons of Liberty before the onset of the Revolutionary War until the most recent reorganization of the U.S. intelligence community, covers the myriad pieces of legislation that have governed the activities of U.S. intelligence, from the National Security Act of 1947, which still constitutes the fundamental law setting up modern U.S. intelligence, to the Intelligence Reform and Terrorism Prevention Act of 2004, which established the new position of the Director of National Intelligence.