This is the first course in a year-long course in microeconomic theory. This course is designed with the two main purposes of giving students a systematic grounding in Microeconomics and preparing them to use economic models in their own research. We will cover the topics of consumption theory, production theory, partial equilibrium, individual decision making with uncertainty, the Arrow-Debreu general equilibrium model, and some basic issues in welfare measurement. While the topics in the course are mathematical, the emphasis is on economic content and research methodology rather than proofs and technical details. Nevertheless, we will use mathematical arguments to help explain the intuition of the theories studied.