This course is a mathematical introduction to strategic thinking and its applications. Ideas such as the core, backwards induction, Nash equilibrium, commitment, credibility, incentives and signaling are discussed and applied to examples drawn from economics, politics, law and history. Applications include auctions, voting, microcredit, labor contracts and market design. Format: Lecture/discussion. Requirements: midterm, final, problem sets and a short project that involves modeling a real world situation as a game. Prerequisites: Economics 251; Mathematics 105 (or permission of the instructor). Enrollment limit: 20 (expected: 15). Preference is given to senior Economics majors.