Evidence-based policy is a concept in public policy stipulating that policy decisions should be based on evidence as opposed to ideological beliefs or common sense. What do we mean by evidence? In this seminar we examine what passes as rigorously established objective evidence, how it is generated and how this evidence has been used so far. In the first part, we focus on the methods of social science in general. In the second part, we gain an overview of different research designs, e.g. surveys, observational studies, laboratory and field experiments. We also examine field experiments that have a randomized design, so-called randomized controlled trials (RCTs). Furthermore, we will learn about the strengths and limitations of these methods and discuss the advantages and disadvantages of these different methods for collecting and analyzing evidence. This is a hybrid course.