Dr. Patricia Lewis (born 1957) is a British and Irish nuclear physicist and arms control expert, who is currently the Research Director for International Security at Chatham House. She was previously the Senior Scientist-in-Residence and Deputy Director at the James Martin Center for Nonproliferation Studies at Monterey Institute of International Studies (MIIS). Before her time at MIIS Patricia was the Director of the United Nations Institute for Disarmament Research (UNIDIR) and the Director of VERTIC.Dr. Lewis publishes widely on all aspects of arms control and disarmament issues and is frequently invited to speak at international conferences.