With the terrorist attacks of 9/11, international attention has shifted to Afghanistan. This event also marked the beginning of a fundamental transformation in the country: It was and is target of an enormous military campaign that toppled the Taliban in a “War on Terror”. With the previous government deposed, a new one had to be built. Guided by a multinational coalition, the Afghan state was quickly reformed, but instabilities and conflicts have not only been inherited but also unintentionally triggered. Even after more than 15 years of international intervention, neither peace nor political stability or security seem to have taken roots in the country. The book takes a closer look at the international state-building regime and evaluates the impact and outlook of such efforts in Afghanistan. In order to facilitate the analysis, the study concentrates on Security Sector Reform (SSR) with special emphasis on the reconstruction of the Afghan military and police. With this, the author presents critical insights into state-building prospects in Afghanistan and introduces an analytical approach that may also be transferred to other cases of state reconstruction.