Book excerpt: During the Cold War, when the United States' intelligence efforts were focused on the Soviet Union, one of the primary tasks of the Central Intelligence Agency was to estimate Soviet defense spending. In Soviet Defense Spending: A History of CIA Estimates, 1950-1990, Noel E. Firth and James H. Noren, who spent much of their long CIA careers estimating and studying Soviet defense spending, provide a closer look at those estimates and consider how and why they were made. In the process, the authors chronicle the development of a significant intelligence analytic capability. Firth and Noren also explain what the CIA has learned since the collapse of the Soviet Union about the USSR's actual military spending during the Cold War.