This article describes the author’s experiences researching three books on espionage history in three different countries and on three different topics. The article describes the foreign intelligence arm of the Ministry for State Security; a global history of secret writing from ancient to modern times; and finally, my current project on U.S. intelligence and technology from the Cold War to the War on Terror. The article also discusses the tensions between national security and openness and reflects on the results of this research and its implications for history and for national security
