In the summer of 2002, the Canadian Taekwondo master Tran Trieu Quan travelled from his Quebec City home to the Dominican Republic to give classes in the popular martial art.
A local black belt, Norberto Taveras, volunteered to be his driver and interpreter. At the end of the visit, Mr. Quan thanked the 26-year-old Dominican. "He told me, 'You know Norberto, you drive very carefully. You calculate everything. But sometimes in life you have to take risks.'"
Mr. Taveras realized Mr. Quan had sized him up and was suggesting he become more assertive in life.
"He made me understand I had potential," recalled Mr. Taveras, who is now a father of two and a Taekwondo instructor in the Dominican capital, Santo Domingo.
"He was a very wise, wise man, with lots of knowledge, not only about Taekwondo but about life."
Mr. Quan left a similar stamp on scores of people. His was not a household name, but in Taekwondo circles he was respected around the world.
When Mr. Quan went missing after the earthquake hit Haiti a month ago, thousands signed up on a Facebook support page and words of sympathy poured in from Manila to Rome to Buenos Aires.
Mr. Quan's remains were identified and his death confirmed on Feb. 12. He was 57.
"What happened is a great tragedy. He was appreciated by a lot of people," said Roy Rolstad, a Taekwondo instructor in Oslo.
An engineer and entrepreneur, Mr. Quan was a 9th degree black belt and the president of the International Taekwon-Do Federation, one of the sport's two main ruling bodies.
His life, unfolding against the backdrop of Vietnam's tumultuous history, was marked by both great achievements and great tragedy.
"He was quite a package," said former Nova Scotia premier Russell MacLellan, a friend and fellow Taekwondo practitioner.
Behind Mr. Quan's soft-spoken, self-effacing manner, Mr. MacLellan said, was a smart, tough man.
"If you were a bully, you'd go after this fellow. He wasn't a big man. But in [Taekwondo]practice, he was a power. He was very quick and had excellent technique."
Mr. Quan was born in Hanoi, two years before the 1954 Geneva Conference split Vietnam in two, creating an exodus to the south of families that didn't wish to live under a communist government.
Mr. Quan grew up with eight siblings in wartime Saigon.
At the time, South Vietnam was one of the first countries where the new Korean fighting system of Taekwondo was introduced, through South Korean soldiers posted there in the 1960s, according to martial-art historian Dakin Burdick.
Mr. Quan first learned Taekwondo when he was 12, from a neighbourhood police instructor, said a brother, Tran Trieu Cung.
By the age of 17, Mr. Quan had earned a black belt and was teaching Taekwondo at his high school, under the sponsorship of one of the martial arts' pioneers, the South Korean Lieutenant-Colonel Kim Bong Sik.
Without proper facilities, Mr. Quan gave instructions on an old tennis court, relying on team-building methods he had learned as a Boy Scout, Mr. Cung recalled.
The war exacted a terrible toll on Mr. Quan's family. His eldest brother died in a B-52 bombing in 1968. His father was a civil servant in the South Vietnamese government. After the communist victory in 1975, life was harder for people associated with the old regime.
Mr. Quan's parents and four of his siblings and their families decided in 1977 to flee Vietnam as boat people. Their ship disappeared at sea and their ultimate fate was never known.
"It was a time of great sorrow and I felt absolutely helpless," Mr. Quan, who rarely dwelled on those events, wrote 30 years later in one of his bulletins as ITF president, where he talked about the need to find peace of mind.
Since 1970, he had lived in Quebec City where he earned a degree in mechanical engineering at Laval University. He found work with the provincial building-code regulator. He started a family and obtained Canadian citizenship.
And he taught Taekwondo, lacing his instruction with a mix of Buddhist, Taoist and Confucian philosophies.
Janel Gauthier, a psychology professor who became a friend and black belt, said Mr. Quan was one of Taekwondo's pioneers in Quebec, opening schools and clubs across the hinterland, including in Innu reserves, where he was credited with helping troubled kids.
He also collaborated with physical-education researchers at Laval University to videotape Taekwondo practitioners to find whether the wave movement, a body bounce typical of ITF moves, effectively added power to kicks and punches.
By the early 1990s, as Vietnam opened up to a free-market economy, Mr. Quan started a consulting firm to help companies that wanted to do business in his native country.