William Bradford Shockley Jr. (February 13, 1910 – August 12, 1989) was an American physicist and inventor. He was the manager of a research group at Bell Labs that included John Bardeen and Walter Brattain. The three scientists were jointly awarded the 1956 Nobel Prize in Physics for "their researches on semiconductors and their discovery of the transistor effect".

Partly as a result of Shockley's attempts to commercialize a new transistor design in the 1950s and 1960s, California's "Silicon Valley" became a hotbed of electronics innovation. In his later life, while a professor of electrical engineering at Stanford University, Shockley became a proponent of eugenics. A 2019 study in the journal Intelligence found him to be the second-most controversial (behind Arthur Jensen) intelligence researcher among 55 persons covered.