A history of winning intelligence practices from the Spanish Armada to Cyberwar that offers timeless, practical lessons we ignore at our peril. According to conventional wisdom, strategic surprise and other intelligence failures are both inevitable and ultimately irrelevant because, at least in international politics and war, military muscle matters more than brains. In Decision Advantage , Jennifer E. Sims counters this argument by investigating the history of intelligence through centuries of international conflict, including the 16th Century's Spanish Armada, two US Civil War battles, the hunt for President Lincoln's assassin, and key diplomatic crises before the two World Wars. Sims dives deep into these events to show that the competitive pursuit of intelligence advantage has been a measurable, buildable, and consequential form of power that can help competitors win against otherwise stronger opponents. From these observations, the author develops a general guide to building intelligence readiness, whether for war, diplomacy, or international manhunts. Refuting arguments that intelligence is a sideshow because intentions are unknowable and predictions risky, she redefines success as gaining information advantages over an adversary, prescribes four practical pathways for gaining them, and confirms what seems to be simple common sense: smart competitors know how to learn, and the ones who learn best tend to win. Thinking of intelligence in this way, Sims argues, adds a moral character to an enterprise that is too often mired in excessive secrecy and tyrannical agendas. By "lifting the veil" on international politics, Decision Advantage shows how good intelligence can lessen the likelihood of wars of misperception and folly. "This lengthy work gives readers a great deal to ponder, particularly Sims's illustration of the critical roles that intelligence gathering and analysis play in determining the course of conflict, invisible though they often are." -- Choice "Sims has produced a thought-provoking book that seeks to bridge intelligence theory and history. The case-studies are engaging and full of detail on the influence of intelligence on military and diplomatic competition, which will be of interest to a broad audience...Sims's book should be read widely." -- Dan Lomas, International Affairs "Jennifer E. Sims's Decision Advantage is an examination of how intelligence has influenced select decision-makers, through three broad periods in history, culminating in a proposed theory of intelligence in international politics...as a historical study of intelligence, the book excels." -- Robin Kemp, H-Net "In Decision Advantage , Jennifer E. Sims seeks to correct both popular misconceptions of how espionage operates and rebut the views of those who dismiss its importance in international politics." -- Mitchell B. Reiss, Intelligence, Strategy and Governance in the Twenty-first Century Jennifer E. Sims is a non-resident Senior Fellow with the Chicago Council on Global Affairs. Before this residency, Sims was a core faculty member and Director of Intelligence Studies in the Security Studies Program at Georgetown University's Walsh School of Foreign Service while also serving as a presidential appointee on the USG's Public Interest Declassification Board (2008-2011) and as a member Director of National Intelligence's Senior Advisory Group. During her more than ten years of US government service, Dr. Sims was Deputy Assistant Secretary of State for Intelligence Coordination (1994-1998) and Intelligence Advisor to the Under Secretary for Management and Coordinator for Intelligence Resources and Planning at the US Department of State (1998-2001). In 1998, Dr. Sims received the Intelligence Community's highest civilian award, the National Distinguished Service Medal, for developing the concept of intelligence Support to Diplomatic Operations (SDO) and implementing it during the Balkan War with the establishment of the first Diplomatic Intelligence Support Center in Sarajevo.