Stephen Bosworth, former U.S. Ambassador to South Korea and special representative for North Korea policy, died on Sunday at the age of 76, Yonhap News Agency reported late on Monday.

As a Korea expert, Bosworth was appointed U.S. special representative for North Korea policy in 2009 by former U.S. Secretary of State Hillary Clinton and served until October 2011. Bosworth also served as a U.S. Ambassador to South Korea from 1997 to 2001 and an executive director for the Korean Peninsula Energy Development Organization (KEDO) from 1995 to 1997.

“I was his deputy in Seoul and had the honor of learning from him valuable lessons about leadership and the art of diplomacy that stayed with me throughout my career,” Evans Revere, Bosworth’s former State Department colleague, told NK News on Tuesday.

“In an era when some of our most noted diplomats seemed to pride themselves on (and be praised for) the amount of crockery they broke and the size of their egos rather than on their ability to get the job done, Steve Bosworth was an ambassador whose effectiveness, dignity, honesty, and sincerity were second to no one,” continued Revere. “I will miss him deeply.  This is a sad moment for American diplomacy.”

David Straub, associate director of the Korea Program at Stanford University’s Walter H. Shorenstein Asia-Pacific Research Center, echoed Revere’s respects for the late ambassador.

“I had the privilege of working for Steve Bosworth from 1999 to 2001 during his tenure as ambassador to Korea. He was one of the three smartest people I ever knew during my 30 years with the Department of State and he was the nicest and most decent and most mature,” Straub told NK News.

Ambassador Jack Pritchard, former U.S. special envoy to North Korea, told NK News that Bosworth’s “dealings with North Korea demonstrated the art of the possible.

“He was able to accomplish what he did by showing and ultimately gaining respect from those he dealt with.”

Pritchard added that Bosworth was a model diplomat who had a truly remarkable career that spanned the Atlantic and Pacific.

Van Jackson, formerly of the Center for a New American Security, said: “I was with him during the U.S.-DPRK talks in 2011. The North Korean side would say things that make you want to pound the table and storm out, yet he would respond with dignity, firmness and tact all at once. He believed in diplomacy, and had a special ability to make it out.”

Jackson, currently associate professor with the Asia-Pacific Center for Security Studies, remembered him as “the consummate diplomat, renaissance man and all-around gentleman.”

Baek Hak-soon at the Sejong Institute in South Korea added that Bosworth always pushed for an emphasis on dialogue with the DPRK.

“Bosworth was one of respected diplomats in Washington. He maintained consistently that the problems of the Korean peninsula, especially North Korea, should be resolved through dialogue and negotiations.”

Bosworth told NK News last October the Obama administration had failed to make a breakthrough on North Korean issues because “we underestimated the extent to which they were already into a political transition of leadership, which made them extremely wary of doing anything.”

“From a U.S. point of view, when they conducted their missile test and then the nuclear test, that was sort of sticking their thumb in our eye. I think, again, you have to broaden the aperture here and see all this as to some extent part of their political transition,” Bosworth said.

Bosworth was born December 4, 1939. He was recently a chairman of U.S-Korea Institute at School of Advanced International Studies of Johns Hopkins University and received the honor of “diplomat of the year” from the American Academy of Diplomacy in 1987.

Bosworth had suffered from prostate cancer, but his exact cause of death has not yet been revealed.

Additional reporting: Chad O’Carroll