Mary Henrietta Kaldor (born 16 March 1946) is a British academic, currently Professor of Global Governance at the London School of Economics, where she is also the Director of the Civil Society and Human Security Research Unit. She also teaches at the Institut Barcelona d'Estudis Internacionals (IBEI). She has been a key figure in the development of cosmopolitan democracy. She writes on globalisation, international relations and humanitarian intervention, global civil society and global governance, as well as what she calls New Wars.
In 1981, Kaldor was a member of the anti-nuclear Labour Party Defence Study Group. She was a founding member of European Nuclear Disarmament, editing its European Nuclear Disarmament Journal (1983–88). She was the founder and Co-Chair of the Helsinki Citizens Assembly, and a founding member of the European Council on Foreign Relations. She also writes for OpenDemocracy.net, belongs to the board of trustees of the Hertie