This chapter introduces the readers to oligopoly and game theory and the applications of game theory to the real world. After reading this chapter and working on the practice questions, the learners should be able to recognize oligopolies in the real world, analyze simultaneous-move games of complete information to determine the dominant strategy of each player (if a dominant strategy exists) and the Nash equilibrium or equilibria of a game, identify real-world applications of the Prisoner’s dilemma and other introductory game theory problems, analyze dynamic games of complete information, and use backward induction to identify the subgame perfect Nash equilibrium.