Foreign intelligence played a number of important roles in the Cold War, but this topic has not received the scholarly attention it deserves. This survey article provides a broad overview of some of the new literature and documentation pertaining to Cold War-era intelligence, as well as the key dimensions of the topic. Despite the continued obstacles posed by secrecy and the mixed reliability of sources, the publication of numerous memoirs and the release of a huge volume of fresh archival material in the post-Cold War era have opened new opportunities to study the role of intelligence in Cold War history. Scholars should explore not only the "micro level" of the problem (the impact of intelligence on specific events) but also the "macro level," looking at the many ways that the Cold War as a whole (its origins, its course, and its outcome) was influenced, perhaps even shaped, by the intelligence agencies of the United States, the Soviet Union, and other key countries. It is also crucial to examine the unintended consequences of intelligence activities. Some interesting examples of "blowback" (effects that boomerang against the country that initiated them) have recently come to light from intelligence operations that the United States undertook against the Soviet Union. Only by understanding the complex nature of the role of intelligence during the Cold War will we be able to come to grips with the historiographical challenge that the topic poses.