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Law of the Sea


Admission requirements

Required course(s):

  • Principles of Public International Law

Recommended course(s):

  • International Dispute Settlement

  • International Environmental Law


The law of the sea is codified in the United Nations Convention on the Law of the Sea (UNCLOS), being the “constitution” of the oceans. We examine the legal regimes regulating the use of the internal waters, ports, archipelagic waters, the territorial sea, the contiguous zone, the exclusive economic zone (EEZ), the continental shelf, the area, and the high seas. We see how States establish their maritime boundaries, and how overlapping boundaries are delimited between adjacent States. We examine the legal definition of islands, rocks, low-tide elevations, installations, ships, vessels, artificial islands, as well as harbour works. We turn our attention to the environmental protection of marine areas both within and beyond any State’s national jurisdiction. The regulation of the search and rescue of migrants at sea is also included. And we pay attention to piracy and other security issues. Finally, we discuss the rules and procedures for the peaceful resolution of international ocean disputes.

NB: This course will not cover ‘maritime’ law, which focuses on commerce and navigation on the high seas and other navigable waters, and the relations between entities and individuals regarding maritime transport, insurance, and liability.

Course Objectives

With this course, you increase your knowledge, and more particularly, you will

  • be familiar with the foundations of the international law of the sea;

  • understand the relevance of the law of the sea for the governance of all maritime zones and the different uses of the sea;

  • be able to define and distinguish the different maritime zones;

  • know the basics of the legal regime of each of these maritime zones;

  • be familiar with the rules on maritime boundary delimitation;

  • understand the rights and duties of States and other actors in the field of marine environmental protection;

  • appreciate the relevance of human rights law for ocean governance;

  • understand the different methods of dispute settlement under the law of the sea.

With this course, you acquire new skills, more particularly, you will

  • have gained experience in preparing a written memorial relating to a law of the sea dispute and in presenting and defending the arguments developed therein orally;

  • be able to respond critically and respectfully to the argumentation put forward in the memorials and oral pleadings of your fellow-students.


Timetables for courses offered at Leiden University College in 2023-2024 will be published on this page of the e-Prospectus.

Mode of instruction

We have seminars twice a week. Before each seminar, please read the relevant section of the compulsory textbook (see ‘Literature’ section below), and any other additional reading.

Assessment Method

  • First, you are asked to write a short reflection paper on the relevance of the law of the sea for ocean governance (this determines 15% of your overall grade).

  • Second, the Moot Court assessment offers you the opportunity to deepen your knowledge through the in- depth and active study of a specific dispute relating to the law of the sea. In teams of two – or individually – you can take on the role of counsel in a case before the International Court of Justice (ICJ) or the International Tribunal for the Law of the Sea (ITLOS). You need to prepare a written memorial (30%) and present and defend the arguments developed therein orally (15%).

  • Third, the final exam (40%) consists of an on-site and open book exam, covering all the materials of the course.

Reading list

You need to purchase Donald R. Rothwell and Tim Stephens, The International Law of the Sea, Hart Publishing, third edition, 2023. This textbook is compulsory. (NB. Not all chapters will be discussed.)

You also need a printed or electronic version of the United Nations Convention on the Law of the Sea, to bring to class and make notes.

Additional articles and other readings will be made available electronically via the course website on Brightspace, or, where allowed under copyright laws, via weblinks.


Courses offered at Leiden University College (LUC) are usually only open to LUC students and LUC exchange students. Leiden University students who participate in one of the university’s Honours tracks or programmes may register for one LUC course, if availability permits. Registration is coordinated by the Education Coordinator,


Otto Spijkers,