Dafydd Williams

Dafydd Williams, known as Dave Williams, is a Canadian physician born May 16, 1954, in Saskatoon, Saskatchewan, who was selected by the Canadian Space Agency in June 1992 and later joined NASA Astronaut Group 15 in 1994. He flew two Space Shuttle missions, STS-90 in 1998, a 16-day neuroscience research flight aboard Columbia, and STS-118 in 2007 to the International Space Station aboard Endeavour, during which he completed three spacewalks totaling 17 hours and 47 minutes, a Canadian record, becoming the third Canadian to walk in space. In 1998 he also became the first non-American to hold a senior management position within NASA, serving as Director of the Space and Life Sciences Directorate at the Johnson Space Center.