The aim of this course is to provide an introduction to the identification and estimation of causal effects using observational data typical of the social sciences. Each year an expert in causal methodologies will be invited to teach this course and the topics can vary from year to year. Some examples of topics covered include propensity score matching, instrumental variable regression, regression discontinuity designs, and fixed effects models. A detailed course description will be provided by each new lecturer before the course starts. The course will offer participants theoretical and applied perspectives on these topics using real-world examples. Lab sessions will demonstrate the implementation of the covered techniques using the software STATA.