Siegfried Flügge was a German theoretical physicist who made contributions to nuclear physics, including articles important to the development of nuclear weapons. He worked in the German Uranverein (nuclear weapons project), 1939. From 1941 onward he was a lecturer at various German universities; he was also a visiting professor at U.S. universities between 1949 and 1953. From 1956 to 1984, he was editor of the 54-volume, prestigious Handbuch der Physik.