Dr. Wilfred Bennett Lewis (generally referred to as W.B. Lewis or simply W.B.) arrived in Canada in 1946 when he replaced John Cockcroft as Director of the Chalk River laboratories. For most of the next three decades he dominated nuclear research and the development of nuclear power in Canada. The outstanding success of the CANDU reactor program, which he led, was his most stunning achievement. Dr. Lewis retired from AECL in September of 1973 and was presented with a book of photographs of important events during his tenure. The following photographs are taken from this collection.