What do intelligence agencies actually do beyond spying, and what is their role in global politics? Circulating Secrets offers a deeply researched look at the secret networks that connect intelligence services across borders. The book offers a comparative study of the intelligence agencies of East Germany, West Germany, Iraq and Egypt, and shows that all four shared important traits and learned from one another. By showing how and why intelligence agencies across many different regime types maintain relations, the book challenges conventional views of intelligence agencies as primarily national actors. Instead, Circulating Secrets presents intelligence as a transnational, collaborative enterprise, which underpins diplomacy, security, and economic exchange, and continues to shape the world order today. Drawing on years of archival research, the book explores secret meetings, training exchanges, covert trade, and the 'intelligence entrepreneurs' who made these connections possible. This title is also available as open access on Cambridge Core.