Game theory is a field of applied mathematics that describes and analyzes interactive decision situations. It consists of a set of analytical tools that predict the outcome of complex interactions among rational entities, where rationality demands a strict adherence to a strategy based on perceived or measured results. This lecture introduces wireless engineers to game theory. In recent years there has been a great deal of interest in applying game theory to problems in wireless communications and networking. Authors Allen Mackenzie and Luiz DaSilva provide students, researchers, and practitioners the tools they need to understand and participate in this work, provide guidance on the proper and improper uses of game theory, and examine future directions and applications of game theory. No familiarity with game theory is necessary; the authors introduce major game theoretic models and results and apply them to networking problems including medium access, routing, energy-efficient protocols, and others.