Environmental peacemaking approaches claim that shared environmental problems provide incentives for groups in conflict to engage in common problem solving. Such cooperation, in turn, might produce spill-over effects, further interdependence, understanding, trust, and eventually peace. In this paper, I present the research design, results, and method-related lessons of a one-year research project on environmental peacemaking. More specifically, the project investigated whether cooperative environmental agreements make shifts towards more peaceful relations between states more likely, and if so under which circumstances. In order to answer this question, I utilised statistical analyses, a qualitative comparative analysis (QCA), and desk-based case studies. The paper discusses several advantages of such a multi-method research design, including a sensitivity to causal mechanisms, improved model specification and case selection practices, and the possible triangulation of results. However, I also identify various shortcomings of the research design, such as conflicts between context sensitivity and generalisability, incoherent results, and communication problems.
