Responsibility is a cardinal concept of law in general, a crucial element for a functioning legal system, and even more for international law. At the same time, we use the term ‘responsibility’ in different ways, and for different implications. In this course, we will explore the most common notions of responsibility in international law, its main elements, and the consequences thereof. Although the state is still the primary subject of international law, given the highly globalised context and the wide array of actors involved in international relations, the course not only focuses on the responsibility of states but also of other actors facing new challenges. 

In that sense, the course is divided into fourth parts: (i) general background (history, definition, codification); (ii) the main elements of international responsibility (internationally wrongful act, attribution, circumstances precluding wrongfulness); (iii) the consequences of international responsibility (duty of performance, cessation, reparation, countermeasures, invocation), and (iv) the implications of international responsibility in other areas of international law (armed conflicts, economic law, environmental and climate change law, international adjudication).