In 1941 Libby received a Guggenheim fellowship to work at , Los Angeles, and director of its Institute of Geophysics and Planetary Physics (from 1962) until his death.He was the recipient of numerous honours, awards, and honourary degrees.He is, since 1963, Director of the Douglas Aircraft Company, and Member of the National Science Foundation's General Commission on Science, the Federal Government and the Academic Institution.Libby is a Physical Chemist, and specialist in radiochemistry, particularly hot atom chemistry, tracer techniques, and isotope tracer work.

Libby resigned from the AEC in 1959 to become Professor of Chemistry at University of California, Los Angeles (UCLA), a position he held until his retirement in 1976.During the late 1950s, Libby and physicist ’s petition for a ban on nuclear weapons.To prove the survivability of nuclear war, Libby built a fallout shelter at his house, an event that was widely publicized.In 1940 he married Leonor Hickey, by whom he had twin daughters.In 1966 he was divorced and married Leona Woods Marshall, a staff member at the RAND Corporation of Santa Monica, Calif.