This class is meant to introduce key concepts and tools in Industrial Organization. We will cover (1) Simple IO theory models of competition. (2) Enrich these models with real-world data by applying tools in demand estimation, including discrete choice models with random coefficients. (3) Methods of estimating production and cost functions, including control function methods. (4) Topics in vertical markets, such as double marginalization and bilateral bargaining, and their application to key service industries. (5) Models of industry evolution and dynamic oligopoly. These models are used to investigate policy debate of innovation and competition.