Wilfrid Bennett Lewis, CC CBE FRS FRSC (June 24, 1908 – January 10, 1987) was a Canadian nuclear scientist and administrator, and was centrally involved in the development of the CANDU reactor.
Starting in the mid-1940s, Lewis directed the development and championed the CANDU system, with its natural uranium fuel moderated by heavy water (deuterium oxide) to control neutron flux.
The CANDU has proven its value for commercial power applications, showing outstanding efficiency and safety records.
From 1955 until 1987, he was the Canadian Representative on the United Nations Scientific Advisory Committee.
In 1994 a biography of Lewis entitled Nuclear Pursuits was published Ruth Fawcett.