This course aims introducing substantial theoretical concepts and tools to be able to formalize and analyze strategic interactions in macro and microeconomics, and beyond to read theoretical and applied scholar articles on decision theory and game theory. Decision theory studies choices that result in either risky or uncertain outcomes, while game theory is the analysis of strategic interactions between rational agents. Both are dynamic fields, with substantial developments and numerous applications in economics (bargaining, taxation, industrial organization), political sciences (voting, government stability, climate policy), philosophy (social norms), biology (evolution, cooperative/aggressive behavior), computer science...