Identifying Threats and Threatening Identities gives a much needed and much overdue voice to the social psychological approach to international relations at a level competing with the major paradigms of realism, liberalism, and constructiv- ism. It highlights the complementarity between psychology and constructivism, both of which focus on the role of ideational factors in explaining and giving meaning to the material world of mainstream international relations. The book highlights contingency and complexity in contrast to the parsimonious but incomplete paradigms of the mainstream field. This virtue is not without its price, however. Rousseau’s numerous dense formulations of multilevel dynamics can be unwieldy at times. His graphs and tables in particular do not simplify or clarify the theory and findings as much or as intuitively as readers might hope or expect. In short, international politics is complex, and Identifying Threats and Threatening Identities, for good and ill, accurately captures that complexity.