{"record":{"aliases":[],"appointmentIds":["japan-f30adec4ab3980"],"appointmentsDataset":"https://chanceries.org/diplomats.json","archivalSources":[],"canonicalUrl":"https://chanceries.org/diplopedia/people/shinsuke-j-sugiyama-33d2bfcb76/","countrySlug":"japan","entityId":"https://chanceries.org/diplopedia/people/shinsuke-j-sugiyama-33d2bfcb76/#person","eventIds":[],"expandedParagraphs":["Shinsuke J. Sugiyama combined diplomatic work with a sustained interest in international law. He studied at Waseda and Oxford and entered Japan’s Foreign Ministry in 1977. His assignments included Washington, Seoul, and Cairo, while his work in Tokyo ranged from treaty affairs to development cooperation and climate negotiations. He led the Asian and Oceanian Affairs Bureau and served as vice minister before his appointment as ambassador to the United States in 2018.","That legal background remained visible in his public diplomacy. At Yale in February 2020, Sugiyama explained Japanese policy through the 1956 Soviet–Japanese declaration and the U.S.–Japan security treaty. He argued that diplomatic legality needed to be joined to substantive justice, rather than reduced to procedural correctness. His academic work extended beyond occasional ambassadorial lectures: he taught international law at Waseda, wrote articles, edited books, and participated in the editing of a Japanese international law journal."],"id":"japan:shinsuke j. sugiyama","identifiers":{},"legacyPersonIds":[],"legacyUrl":"https://chanceries.org/diplomat-33d2bfcb76e808bee778.html","name":"Shinsuke J. Sugiyama","notes":[],"paragraphSources":[["sugiyama-icas"],["sugiyama-icas","sugiyama-yale"]],"profileUrl":"diplomat-33d2bfcb76e808bee778.html","relatedEvents":[],"relatedPeople":[],"relationships":[],"researchStatus":"reviewed","reviewedOn":"2026-10-28","revision":"20edf586405fe53b","sources":[{"accessedOn":"2026-10-28","date":null,"id":"sugiyama-icas","locator":"Biographical profile","publisher":"Institute for Corean-American Studies","title":"Shinsuke J. Sugiyama","type":"official-biography","url":"https://www.icasinc.org/bios/Sugiyama_s.html"},{"accessedOn":"2026-10-28","date":"2020-02-14","id":"sugiyama-yale","locator":"Report of February 12 lecture","publisher":"Yale University, MacMillan Center","title":"“Japan’s Foreign Policy and International Law” with Ambassador Shinsuke J. Sugiyama","type":"primary-record","url":"https://macmillan.yale.edu/stories/japans-foreign-policy-and-international-law-ambassador-shinsuke-j-sugiyama"},{"accessedOn":"","date":"2022-04-27","id":"mission-f50179f97ae0f0cde5fa","locator":"Sugiyama ambassador appointment January 2018; foreign-minister adviser February 2021","publisher":"","title":"Kikkoman announcement of directors: Shinsuke Sugiyama biography","type":"Mission record","url":"https://www.kikkoman.com/en/finance/library/pdf/20220427e_2.pdf"},{"accessedOn":"","date":"2020-12-25","id":"mission-dc4249348c63c90fe0df","locator":"Signed official letter says duties end at the end of January 2021","publisher":"","title":"Ambassador Sugiyama farewell letter, 25 December 2020","type":"Mission record","url":"https://www.iwojimaassociation.org/wp-content/uploads/2021/03/BlackSandsV12.1.2021.pdf"},{"accessedOn":"","date":"Accessed 21 October 2026","id":"mission-8314546c735d20419052","locator":"Sugiyama and Lighthizer signed trade and digital-trade agreements October 7, 2019","publisher":"","title":"U.S.-Japan Trade Agreement Text","type":"Mission record","url":"https://ustr.gov/countries-regions/japan-korea-apec/japan/us-japan-trade-agreement-negotiations/us-japan-trade-agreement-text"}],"topics":["international law","climate diplomacy","U.S.–Japan alliance"]},"schemaVersion":1}