In the wake of the adoption by the International Law Commission of a complete set of articles on state responsibility in international law in 2001, this collection assembles a number of essays tracing key debates which have marked the evolution of this field over the last fifty years. These include explorations of the general theory of state responsibility (link between ’primary’ and ’secondary’ rules, the place of due diligence, the link between liability and wrongfulness), the consequences of an internationally wrongful act (nature of remedies, suitability of countermeasures, third states and the shift from bilateralism to community interests in the law of state responsibility), the debate over criminalizing state responsibility, and the continuing relevance of the law of injuries to aliens. The collection also contains a series of essays offering critical perspectives on state responsibility, including feminist and developing world perspectives. It is completed by an extensive and up-to-date bibliography.