Carsten Staur Shared responsibility: The United in age of globalization Montreal & Kingston: McGill-Queen's University Press, 2013. 336 pp., $100.00 (cloth) ISBN 9780773542945Does United (UN) have strength and drive necessary to make decisions and implement solutions to problems that do not respect national boundaries (260)? This is question Carsten Staur, Denmark's permanent representative to United in Geneva, tries to answer in Shared Responsibility. The diplomat paints comprehensive picture of our world and threats weighing on it-for example, global warming, terrorism, and armed conflicts. He asks whether UN is still relevant to these existential challenges in twenty-first century. His answer is subtle.Through well-documented, informed, and supported argumentation, Staur explains why UN system remains best platform for dealing with four global mega-trends: (1) fundamental in global power structure, with some emerging economies developing into new key players; (2) an increasingly pronounced struggle between different global value systems; (3) new non-state actors wanting greater say in decision-making processes; and (4) climate mitigation strategies leading to dramatic changes in global economy. Concerning last point, he offers some hope for future, reminding reader of success of 1987 Montreal Protocol on use of ozone-depleting products. Through international goal-setting and framework approach, Staur argues, the depletion of ozone layer has now been stopped, and... ozone layer will most probably be fully restored by about 2050 (237). The Montreal Protocol thus constitutes a model solution to global environmental issue that has increasingly been seen as applicable in other fields, including climate change (237).In chapter about sustainable development, as in eleven others, Staur takes time to provide history of each of four challenges. He explains structure and evolution of UN system going as far back as League of Nations. In chapter dedicated to peacekeeping, he returns to UN's first operation in Palestine (the UN Truce Supervision Organization, established in 1948). One appreciates this historical depth as well as fluidity and simplicity of Staur's writing, which make it possible for non-specialists to learn great deal about United Nations. The author does an excellent job, for instance, of explaining why it is so difficult to reform Security Council and why condemning genocide and war crimes is not as simple as we might expect.Valuable as it is to non-specialists, Shared Responsibility is less useful to experts. There is nothing really new in this study for those who know and study UN system. For this reason, it is regrettable that Staur does not elaborate on the informal of play in United Nations (39). As an insider with many years' experience working within UN system, diplomat is ideally situated to reflect on nature, prevalence, and resonance of these unwritten rules (51), which remain inaccessible to outside researchers. Indeed, Staur frequently refers to these without making them explicit. Where do they come from? Who applies them? What happens if member state or UN official does not follow them? Have they changed over time?If these questions remain underdeveloped, so too does question of recruitment and staffing within UN system. …