William Carpentier (born 1935/36, Edmonton, Alberta)[1][2] is a Canadian-American physician best known as the flight surgeon assigned to the United States' Apollo 11 mission, the first crewed spacecraft to land on the Moon.

Both Carpentier and NASA engineer John Hirasaki – who had come into contact with Moon dust – were confined with the astronauts for their 21-day quarantine.

[4] During travel on Air Force One he would be registered by crew into the flight manifest under the initials "WFP" for "world famous physician", a moniker that would stay with him for life.

[4] In 1973, after completing a fellowship in nuclear medicine at Baylor University,[4] Carpentier entered the private sector as a researcher at Texas' Scott & White Healthcare, spending thirty years there before retiring in 2003.

[3] Carpentier was decorated with the Presidential Medal of Freedom for his work on Apollo 13 and, in 2013, received the University of British Columbia Alumni Award of Distinction.