This chapter presents some closing thoughts on the concepts discussed in the preceding chapters of the part two in this book. The part two of the book examines three contributions that specifically address the issue of causal claims: comparative case study methodology on the privatization of security; qualitative case analysis on armed conflict; and geospatial analysis on the emergence of violent conflict. It explains the variation in degree and nature of privatization of security in four different countries: France, Germany, the United Kingdom and the United States. The book seeks to investigate the relationship between reduced availability of natural resources and the advent and intensity of violent conflict. It suggests Qualitative Comparative Analysis (QCA) as an appropriate method to examine whether or not to participate in the 2003 Iraq War. The advantage of QCA is that combinations of variables at different levels can point to causal pathways, thus allowing for the identification of the complementarity of theories.