William Wesley Peters (June 12, 1912 – July 17, 1991) was a noted architect and engineer, apprentice to and protégé of Frank Lloyd Wright.

Born in Terre Haute, Indiana, Peters was educated at Evansville College (now the University of Evansville) and the Massachusetts Institute of Technology. He then became Wright's first apprentice, joining the Taliesin Fellowship in 1932, and remained extremely loyal to the Wright organization throughout his entire career.

Among his accomplishments were assisting Wright in the construction of Fallingwater and the Johnson Wax administration building in Racine. Peters was responsible for the structural designs of the Guggenheim Museum and for the laboratory tower at Johnson Wax, among many other projects. Peters and Taliesin Associates are credited with the design for the Kaden Tower in Louisville, Kentucky and the San Jose Center for the Performing Arts in San Jose, California.

Peters also designed the Pearl Palace in Iran on request from Princess Shams Pahlavi.

In 1935 he married Wright's adopted daughter, Svetlana (who died in an automobile accident in 1946, along with their son Daniel). Peters raised their other son, Brandoch, on his own. Peters was later briefly married to Svetlana Alliluyeva, the youngest child and only daughter of Joseph Stalin, in a union arranged by Wright's widow, Peters's mother-in-law, and Fellowship matriarch Olgivanna Wright. The couple had a daughter, Olga (now Evans).

In 1990, he gave an interview to Wolfgang von Freeden from Luebeck, Germany about his life and work, including his part in realising Tehran's "Pearl Palace" with the help of glass craftsmen from Murano, Italy.

Peters served as Chairman of the Frank Lloyd Wright Foundation from 1985 to 1991. He died in Madison, Wisconsin.