This course explores long run economic growth, as opposed to short run fluctuations in economic growth arising from business cycles. Motivated by stylized facts from both cross-country and time series data, the course considers the following types of questions: Why are some countries so rich while others are so poor? What explains the heterogeneity in the growth experience across countries, with some growing at a moderate pace over long periods, others growing rapidly over shorter periods, and yet others stagnating. Investigation of such questions is guided by the neoclassical growth model and modern theories of endogenous growth including variety expansion and quality ladder models. As the models are fleshed out, topics covered may include, but are not limited to: investment, technological progress and its relationship to research and development; education, health and population; the role of government and institutions; and the role of natural resources. Prerequisite: ECON 202 or ECON 306.