He also served as the acting Assistant Secretary of State for East Asian and Pacific Affairs from January to June 2021.

Back in Washington, he was appointed Director of the Office of Korean Affairs and served in the position from August 2006 to July 2008.

On July 31, 2008, he was appointed Special Envoy for the Six-Party talks and accorded the rank of an ambassador after confirmation of nomination by the U.S.

[13][14] Kim completed his assignment to South Korea in late October 2014 and returned to the United States, where he was expected to continue to work on diplomacy involving East Asia.

Jonathan Karp, executive director of Asia Society, said Kim has done a lot to advance relations between the U.S. and Korea as a representative of the Obama administration.

[20] Kim, while Ambassador to the Philippines, led a delegation of American diplomats to hold talks with North Korean officials in Panmunjom in late May 2018.

[23] President Joe Biden announced on May 21, 2021, that he would serve as the U.S. special envoy for North Korea.

[24] Kim retired in December 2023 to serve as an adviser for South Korean automaker Hyundai.