Paul Walker is the International Director of the Environmental Security and Sustainability (ESS) Program for Green Cross International (GCI) and manages the Washington, DC, office for GCI and its US national affiliate, Global Green USA. The ESS Program, formerly known as the Legacy of the Cold War Program, is an international effort to facilitate and advocate the safe and sound demilitarization, nonproliferation, and remediation of nuclear, chemical, biological, and conventional weapons stockpiles. Walker is a former Professional Staff Member of the Armed Services Committee in the US House of Representatives where he served as a senior advisor to the chairman and full committee. Walker holds a Ph.D. in security studies from the Massachusetts Institute of Technology, an M.A. from Johns Hopkins School for Advanced International Studies, a Russian Honors Certificate from the Defense Language Institute of the West Coast, and a Post-Doctoral Fellowship from the Center for Science and International Affairs at Harvard University. He is also a Vietnam-era US Army veteran. Walker has worked, spoken, and published widely in the areas of international security, threat reduction, nonproliferation, and weapons demilitarization for over three decades; and took part in the first on-site inspection by US officials of the Russian chemical weapons stockpile at Shchuch'ye in the Kurgan Oblast in 1994. Since that time, he has worked closely with the Organization for the Prohibition of Chemical Weapons (OPCW), US and Russian officials, the Cooperative Threat Reduction (CTR) Program, the G-8 Global Partnership, and other multilateral regimes to help foster cooperative, timely, and safe elimination of nuclear, chemical, and biological weapons and related systems. In December 2009 at the 14th Conference of the States Parties in The Hague, he led the effort to establish the CWC Coalition, an international NGO network to support the Chemical Weapons Convention and OPCW. He is also a founding member of the Fissile Material Working Group (FMWG) which supported the 2010 Nuclear Security Summit. Recent articles include "Abolishing Chemical Weapons: Progress, Challenges, and Opportunities" in Arms Control Today (November 2010) and "The Legacy of Reykjavik and the Future of Nuclear Disarmament" (with Jonathan Hunt) in the Bulletin of the Atomic Scientists (December 2011).