What The project aims to develop a set of methodological tools that enable social scientists to engage in more rigorous study of causal mechanisms using in-depth case studies than are possible using existing methods. Causal mechanisms are what link causes and outcomes together in productive relationships. Mechanism-focused research enables us to gain a better understanding of how things work and under what conditions in real-world cases. Unfortunately, most existing methods black-box causal mechanisms. The monograph will first develop a clear definition of causal mechanisms that focuses on making explicit the activities of entities that link parts together, followed by the development of new ideas about what types of empirical material can act as evidence of the operation of mechanisms Why Current methods for studying mechanisms in the social sciences black-box the actual process. The goal of the project is to develop a methodological framework that enables us to open this black-box, offering insights into how things work in real-world cases. In contrast, most existing methods for studying causal relationships in the social sciences focus on 'one-size-fits-all' generalizations about average causal effects. However, these cross-case inferences tell us nothing about what is going on in particular cases. The mechanistic framework will be particularly relevant for policy evaluation, enabling research on how policy interventions work within actual cases instead of using quasi-experimental frameworks that compare input/output across cases. How The core of the work of the project will be to develop a set of practical methodological tools. This will require considerable conceptual work by the author over the course of the year-long grant period. To explore the efficacy of different ideas developed, I will present the research to other methodological experts at international conferences both in political science, international relations, and policy evaluation. An important component in developing the framework will also be in engaging with ph.d. students in methodological courses that I will be teaching both in Denmark and internationally. In these courses, the developing framework will be discussed, and its efficacy will be evaluated in relation to their ph.d. projects. SSR The project will have significant value-added for social scientists, and for practical policy evaluators. For social scientists, it will empower a new generation of mechanism-focused research that makes different types of causal claims (process) that are evidenced using different types of empirical material (mechanistic evidence) than existing methods. The project will also have significant value-added for the field of policy evaluation. There is already significant interest in mechanism-focused research as an alternative to experimental (random controlled trials) methods in evaluation, but the current methods have only scratched the surface. This project will enable policy evaluators to answer questions related to how an intervention works and under what conditions.