The Philip C. Jessup International Law Moot Court Competition — universally known as "the Jessup" — is the world's largest and most prestigious international law moot court competition. Each year, over 700 teams from more than 100 countries compete in a simulation of a dispute before the International Court of Justice (ICJ). For law students interested in international law, public international law careers, or global advocacy, the Jessup represents both the ultimate test and the ultimate credential.
Winning the Jessup — or even reaching the international rounds in Washington, D.C. — signals to employers, academics, and the international legal community that you can research, write, and argue at an elite level on complex questions of international law.
The competition was founded in 1959 and named after Philip C. Jessup, a distinguished American jurist who served on the International Court of Justice from 1961 to 1970. Jessup was also a professor at Columbia Law School and a diplomat, embodying the intersection of legal scholarship and international practice that the competition seeks to cultivate.
The International Law Students Association (ILSA) has administered the competition since its founding. What began as a small American competition grew steadily throughout the Cold War era, expanding internationally during the 1970s and 1980s as international law gained prominence in legal education worldwide.
Key milestones:
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Each September, ILSA releases the annual "Jessup Problem" — a hypothetical dispute between two fictional nations before the ICJ. The problem typically involves 3-5 complex issues of public international law. Recent problems have addressed topics including:
State responsibility and attribution
Use of force and self-defense
International environmental law
Human rights and treaty obligations
Law of the sea
International humanitarian law
Sovereign immunity
The problem is designed so that strong arguments exist on both sides of each issue. There is no "correct" answer — the competition rewards depth of analysis, creative argumentation, and mastery of international legal authorities.
Teams must submit two memorials — one for the Applicant (the state bringing the claim) and one for the Respondent (the state defending against it). Memorials are the Jessup equivalent of appellate briefs and are scored separately from oral arguments.
Memorial structure:
Statement of Jurisdiction
Statement of Facts
Statement of Issues
Summary of Pleadings
Written Pleadings (the substantive legal arguments)
Prayer for Relief
Memorial scoring criteria:
Knowledge of applicable international law
Proper use of international legal authorities
Persuasiveness of arguments
Organization and structure
Grammar, style, and citation format
Memorials are due in January and typically count for a significant portion of the overall team score at nationals and internationals.
Master the sources of international law. Article 38 of the ICJ Statute lists the primary sources: international conventions, international custom, general principles of law, and subsidiary sources (judicial decisions and scholarly writings). Know where to find each:
Treaties: United Nations Treaty Series (UNTS), specific treaty databases
Custom: State practice compilations, ILC Draft Articles
ICJ and ITLOS decisions: ICJ Reports, ITLOS case database
Scholarly works: Recueil des Cours, leading treatises
Read past Jessup problems and winning memorials. ILSA provides access to prior years' materials. Study how winning teams structured their arguments, handled ambiguous facts, and addressed counter-arguments.
Identify every issue in the problem. The Jessup problem contains hidden issues — questions the problem raises implicitly that strong teams will identify and address. Read the problem 10+ times. Discuss it with teammates, faculty advisors, and anyone with international law expertise.
Start with comprehensive outlines. Before writing prose, map out every argument and sub-argument for each issue. Identify the strongest authorities for each point.
Write Applicant and Respondent simultaneously. Understanding the opposing arguments strengthens both memorials. Your Respondent memorial should answer the best version of the Applicant's arguments, and vice versa.
Follow ILSA's memorial rules precisely. Word limits, citation format, cover page requirements — violations result in point deductions. Read the Official Rules multiple times.
Edit aggressively. Great Jessup memorials read as though every sentence was deliberated over. Cut redundancy, sharpen language, and ensure every paragraph advances your argument.
Anticipate questions. For each argument you make, list 10 questions a judge might ask. Prepare concise, direct answers. The most common Jessup questions target:
Distinguishing unfavorable precedent
Explaining why a general principle applies to the specific facts
Addressing policy implications of your legal position
Handling hypotheticals that test the limits of your rule
Practice under realistic conditions. Find faculty, alumni, or practitioners willing to serve as practice judges. Simulate full 20-minute arguments with active questioning. Record yourself and review.
Master the procedural conventions. ICJ courtroom protocol matters at the Jessup. Address judges correctly, manage time with grace, and maintain the level of formality that distinguishes international advocacy.
Jessup participation and success opens doors across international legal careers:
International organizations — The UN, ICJ, ICC, and international tribunals recognize Jessup achievement
International law firms — White & Case (the competition's longtime sponsor), Freshfields, Linklaters, and other firms with international practices recruit heavily from Jessup participants
Government — Foreign ministries and international affairs departments value the competition
Academia — Many international law professors are former Jessup competitors or coaches
The Jessup alumni network spans thousands of practitioners across the globe, creating professional connections that persist throughout careers.
If international law is your focus, consider these complementary experiences:
Willem C. Vis Moot — International commercial arbitration (different skill set but complementary subject matter)
Telders International Law Moot Court — European-focused public international law
Manfred Lachs Space Law Moot — Emerging area with growing professional relevance
ICC Moot Court Competition — International criminal law
For a broader overview of available moot court competitions, see our competition guide. And for those who want to understand the fundamental differences between moot court and trial advocacy, our moot court vs mock trial comparison explains how the two activities complement each other.
The oral advocacy skills that distinguish top Jessup advocates — structured argumentation, composure under questioning, and the ability to think on your feet — are built through consistent practice. Mock Trial Online provides an AI-powered courtroom simulation where you can practice legal reasoning and oral advocacy against responsive AI judges and opponents. While the subject matter differs from international law, the core advocacy mechanics transfer directly.
