Five hundred episodes in, the format has not changed: one speaker, one subject, one sustained explanation. Speakers introduce themselves by name and standing, then get to work. There is no interviewer, no cold-open teaser, no music bed to fill the pauses. Michael Wood, a barrister in London working mainly in public international law, devotes a lecture to Article 16 of the Articles on State Responsibility. He is careful about vocabulary. Complicity, he notes, is a criminal-law term the Commission deliberately avoided during second reading, and he cites James Crawford on why domestic analogies rarely help. He closes by naming the hard cases: shared intelligence, provided weapons, military assets, transferred detainees. Elisa Morgera, UN Special Rapporteur on Climate Change and Human Rights, traces how international environmental law and international human rights law developed on parallel tracks and have since converged, extending into the law of the sea and climate change law. Her assessment of treaty implementation is blunt. Open-ended obligations have allowed states to under-deliver, and decades of lawmaking have left biodiversity loss, climate breakdown, and toxic pollution unresolved and tangled up with economic inequality. Penelope Ridings, a member of the International Law Commission and former Chief International Legal Advisor from New Zealand, appears twice. One lecture covers ICSID annulment procedure, the grounds under Article 52, the private deliberations of ad hoc committees, the 120-day deadline, and her conclusion that the mechanism is a limited safeguard balancing finality against fairness. The other breaks the WTO's Multi-Party Interim Appeal Arbitration Arrangement into its name, word by word, to explain what it is and what it is not. Cymie Payne, a professor at Rutgers University and chair of the IUCN World Commission on Environmental Law's Ocean Law Specialist Group, took part in negotiating the BBNJ Agreement and reviews its impact-assessment and technology-transfer provisions. She ends on the treaty as evidence that multilateralism still functions. Gina Romero lectures in Spanish on the rights to peaceful assembly and association, listing the protected forms, from marches and vigils to flash mobs and single-person protests, and holding that freedom is the rule and restriction the narrow exception. The register throughout is measured and technical. Arguments build by enumeration and comparison rather than emphasis. Transcripts and related materials are noted as available through the Library's site, which suits anyone who wants to follow the citations afterward.