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A light skin toned man with short, dark and straight hair is facing the camera smiling with his mouth closed. He is wearing glasses and a dark colored button up shirt. The photo is black and white and the background features two circles, one which is yellow and the other blue.

Sejong Youn

Leaders Asia-Pacific 2023


Co-Founder and Director, Plan 1.5


Republic of Korea



Sejong Youn is the co-founder and director of Plan 1.5, a non-profit organization that advocates for better and stronger climate policies in key sectors like energy, industry, finance, and transportation. He formerly worked at Solutions for Our Climate, a non-profit climate organization in Korea, where he oversaw the Climate Finance Program, which focused on phasing out coal financing from public and private financial institutions. In 2020, Sejong represented the 19 activists of the Youth4Climate Action group in filing a constitutional case against the government and the national assembly before the Korean Constitutional Court, demanding better climate mitigation policies. He is a lawyer by profession, and he spent his early career practicing law in the fields of environmental regulation and international dispute resolution. Sejong’s work is driven by the belief that expanding the consensus on the urgency of the climate crisis will lead to meaningful improvements in the way we deal with the issue.