 When one thinks about international law, various images and ideas may pop up in your mind. You may think at war and peace between nations, ongoing humanitarian crisis or other global issues like global warming or the protection of the environment. You may also think at the protection of basic human rights, from the freedom of speech and of demonstration to the right to food or the promotion of social rights for workers. Or more dramatically, you may think at despicable international crimes in the context of violent uprisings or acts of terrorism. You may think also at more personal dramatic events that affected your family in recent years or at more distant events that made history and allowed for instance for your parents or your grandparents to meet or events that forced your family to migrate. On a more peaceful note, you may just think at your latest long-distance flight, getting a visa at the embassy of the country you visited or at the fruits from exotic places that you bought yesterday at the supermarket. Maybe your employed or someone in your family is employed by a large transnational corporation and you've been living abroad because that company made investments there. Or you have sailors in your family, commercial pilots or engineers working on offshore oil platforms. Or just take your smartphone and look at it and imagine, besides of course the incredible engineering and technology that made it, imagine the amount of law that was indeed going into it, not only the fact that you bought it and that you have also contracted with a phone company, which are largely issues of domestic law, but also the oceans. The phone has travelled after having been manufactured. The minerals that had to be extracted to make the components and that were exported. The patents that protects the software in your phone in all jurisdictions. The agreements that have been contracted in order for the data that you download to travel around the planet at the speed of light, etc. As much as our daily lives are constantly influenced and shaped by rules of domestic law that go most of the time unnoticed, they are also increasingly influenced and shaped by rules of international law. And at a time of globalisation, this does not come as a surprise. The more we interact with each other, the more we need common rules to sustain that interaction and to make it predictable. Law mediates between us and offers us a common ground for action. And the complexity resulting from interaction calls for more law. And what is that law that transcends national settings? How does it come to existence? How can it be upheld? What can be done when it is not respected? And also, when you look around and see how much international law is at the same time hypocritically invoked and constantly disregarded by governments, is it really law? Is it possible to have international law as law? Or are international relations actually governed by nothing else but power and might? Would international law offer the best illustration of the well-known thought of Blaise Pascal, who famously wrote that, unable to make what is just strong, we made what is strong just? And where is justice in this world? Is not justice the purpose of any law? Those are the kind of questions we are going to try to answer in this course. Or at least, the course will help you, I hope, to have a more informed and articulate view on those fundamental questions that I just raised. And those questions will be looming large throughout the course, despite the fact that, as I started by recalling, we are actually surrounded by international law all the time.