Sangkoo Yun is a graduate of the School of Architecture at Syracuse University in New York and president of Dongsuh Corp., an architectural materials trading and engineering firm. He is involved in many civic organizations with a special interest in preservation of cultural heritage.

A Rotarian since 1987, when he was a charter member of the Rotary Club of Sae Hanyang, Yun has served RI as a director, convention Host Organization Committee chair, Future Vision trainer, Rotary coordinator trainer, committee member and chair, resource group zone coordinator, assistant moderator, and training leader. He has led the Keep Mongolia Green project since he was district governor in 2004-05.

He and his wife, Eunsun, are Rotary Foundation Benefactors and Major Donors and members of the Arch Klumph Society and Bequest Society.