Book excerpt: An Intelligence failure can be defined where there was intelligence available about a particular event, but either it was not collected or was mishandled later in the assessment cycle, as opposed to the failure of an intelligence operation. The Historical Dictionary of Intelligence Failures covers the history of intelligence failures through a chronology, an introductory essay, an extensive bibliography, and over 100 cross-referenced dictionary entries on the Ardennes Offensive, the Six Day War, and the Cuban Missile Crisis, the Prague Spring, the Arab Spring, 9/11. This book is an excellent access point for students, researchers, and anyone wanting to know more about the intelligence industry.