Here, for the first time, is a comprehensive guide to the literature of ancient intelligence. The entries present books and periodical articles in English, French, German, Italian, Spanish, Polish, and Dutch--with annotations in English. These works address such subjects as intelligence collection and analysis (political and military), counterintelligence, espionage, cryptology (Greek and Latin), tradecraft, covert action, and similar topics (it does not include general battle studies and general discussions of foreign policy).