Hans M. Kristensen is Director of the Nuclear Information Project at the Federation of American Scientists in Washington, D.C., where he is responsible for researching and documenting the status and operations of nuclear forces of the nine nuclear-armed states. He is a frequent advisor to the news media on the status of nuclear forces and policy. Kristensen is co-author of the bi-monthly FAS Nuclear Notebook column in the Bulletin of the Atomic Scientists and the World Nuclear Forces overview in the SIPRI Yearbook, both of which are some the most widely used reference material on the status of the world’s nuclear arsenals. Prior to his current position, Kristensen was a consultant to the Nuclear Program at the Natural Resources Defense Council in Washington, D.C. (2003-2005), and Program Officer at the Nautilus Institute in Berkeley, CA (1998-2002). He was born in Denmark.