Born out of a small research program that began in 1939, the Manhattan Project brought together the cream of the scientific community and the military to create and perfect a weapon more powerful than any the world had known. Racing against time as the war raged in Europe and Asia, and against our enemies, whom we feared were pursuing similar ends, the Project would eventually employ more than 125,000 people and cost a total of over $2 billion—and the entire operation was conducted under a shroud of secrecy, at remote sites around the country.This groundbreaking book—the first of its kind—collects the writings and thoughts of the original participants in the Manhattan Project, along with pieces by the most important historians and interpreters of the subject.