Siegfried S. Hecker (born October 2, 1943) is an American metallurgist and nuclear scientist. He served as Director of the Los Alamos National Laboratory from 1986 to 1997 and is now affiliated with Stanford University, where he is research professor emeritus in the Department of Management Science and Engineering in the School of Engineering, and senior fellow emeritus at the Freeman Spogli Institute for International Studies. During this time, he was also elected a member of the National Academy of Engineering (1988) for outstanding research on plutonium and the forming of materials, and for leadership in developing energy and weapons systems. Biography Early life Hecker's parents came from Sarajevo, Bosnia and were moved during World War II to Tomaszew, Poland, where Hecker was born. When his father had not returned from the war at the Eastern Front, his mother remarried and settled in Rottenmann, Austria. The family emigrated from Styria to the US in 1956. Education Hecker completed his Bachelor of Science in Metallurgy in 1965, his Master of Science in Metallurgy in 1967, and his Doctor of Philosophy in Metallurgical Engineering in 1968, all from Case Western Reserve University. He then spent two years as a postdoctoral appointee at the Los Alamos National Laboratory. Professional career Hecker began his professional career as a senior research metallurgist with the General Motors Research Laboratories in 1970. Los Alamos After Hecker's return to the Los Alamos National Laboratory, he led the laboratory's Materials Science and Technology Division and Center for Materials Science. He then served as the fifth Director of the Los Alamos National Laboratory from 1986 till 1997 and was a Los Alamos Senior Fellow until 2005. Stanford University He first came to Stanford University as a visiting professor in 2005. In 2007 he became co-director of the Stanford University Center for International Security and Cooperation (CISAC) in the Freeman Spogli Institute for International Studies and held this post until 2012. Other activities Nuclear Threat Initiative Hecker also acts as advisor to the Nuclear Threat Initiative board of directors and belongs to the advisory council of CRDF Global, an independent nonprofit organization that promotes international scientific and technical collaboration. Visits to North Korea He has visited North Korea frequently in an unofficial capacity to assess the plutonium program at the Yongbyon Nuclear Scientific Research Center (once every year since 2004). In November 2010, Hecker visited the Yongbyon nuclear facility and reported