Since the attacks of 9/11, the United States intelligence community has undergone an extensive overhaul, including the formation of the Office of the Director of National Intelligence. This book explores the history of intelligence and security, presenting a comprehensive examination of the pillars of American intelligence systems-collection, analysis, counterintelligence, and covert operations-and demonstrates how these work together. In addition, the text covers law and ethics, writing and briefing for the intelligence community, and emerging threats and challenges.