Spencer R. Weart, born in 1942, received a B.A. in Physics at Cornell University in 1963 and a Ph.D. in Physics and Astrophysics at the University of Colorado, Boulder, in 1968. He then worked for three years at CalTech as a Fellow of the Mt. Wilson and Palomar Observatories, publishing papers in leading scientific journals. In 1971 Dr. Weart changed his field, enrolling as a graduate student in the History Department of the University of California, Berkeley. In 1974 he took up his present post as Director of the Center for History of Physics, American Institute of Physics, the oldest institution dedicated to preserving and making known the history of a scientific discipline. Dr. Weart has written two childrens science books and wrote or co-edited seven other books, including Scientists in Power (a history of the rise of nuclear science, weapons, and reactors in France); Leo Szilard: His Version of the Facts (edited correspondence); a collection of essays on the history of solid-state physics; Nuclear Fear: A History of Images; and Never at War: Why Democracies Will Not Fight One Another. He also produces and edits an award-winning Website with historical exhibits. Dr. Weart has taught history of science courses at the Johns Hopkins University, the New School-Lang College, and Princeton University. He has served as Treasurer and Council member of the History of Science Society.