This paper distills those features of Chaos theory essential to military decision makers. The new science of Chaos examines behavior that is characterized by erratic fluctuations, sensitivity to disturbances, and long- term unpredictability. This paper presents specific ways we can recognize and cope with this kind of behavior in a wide range of military affairs. Designed for courses at the various war colleges, the paper makes three new contributions to the study of Chaos. First, it reviews the fundamentals of chaotic dynamics; the reader needs no extensive prerequisites in mathematics. Much more than a definition-based tutorial, the first part of this paper builds the reader's intuition for Chaos and presents the essential consequences of the theoretical results. Second, the paper surveys current military technologies that are prone to chaotic dynamics. Third, the universal properties of chaotic systems point to practical suggestions for applying Chaos results to strategic thinking and decision making. The power of Chaos comes from this universality: not just the vast number of chaotic systems, but the common types of behaviors and transition s that appear in completely unrelated systems. In particular, the results of Chaos theory provide new information, new courses of action, and new expectations in the behavior of countless military systems. The practical applications of Chaos in military technology and strategic thought are so extensive that every military decision maker needs to be familiar with Chaos theory's key results and insights.