This unit views applications of elementary game theory to international relations. It is noted that of all the significant world problems, the nuclear arms race has proved one of the most intractable. The main concern of the module is to investigate a possible solution to the arms race, based on extending the classic two-person game of Prisoner's Dilemma and allowing for sequences of moves. An analysis of the generated model is followed with considerations of possible extensions to both new games and different scenarios. The material is designed to help students: (1) understand some basic concepts in game theory; (2) apply concepts to arms race analysis and other two-person conflict situations; (3) derive consequences of extended play of different games and scenarios; (4) illustrate consequences graphically; (5) state policy implications of an analysis; and (6) justify normative judgments based on analysis. The module contains exercises, with solutions, and concludes with a listing of references. (MP)