Qualitative methods play a crucial role in natural experiments. Indeed, I argue that the knowledge of context and detailed information on process that qualitative methods often facilitate is crucial for the method’s persuasive use. The goal of this chapter is to develop this idea systematically, by providing a framework for thinking about the general utility of qualitative evidence in natural experiments while also providing several examples from recent social-scientific research. This in turn may help provide the foundation for better use of qualitative methods in future natural-experimental research.

The topics discussed in this chapter relate not just to analysis—the focus of this Part II of the book—but also to the discovery and evaluation of natural experiments (the focus of Parts I and III, respectively). However, the central interplay between qualitative and quantitative analysis in many successful natural experiments suggests that this material is best presented in conjunction with the previous two chapters on quantitative analysis.