Sir Ian Brownlie CBE QC FBA (19 September 1932, Liverpool – 3 January 2010, Cairo) was a British practising barrister, specialising in international law. After an education at Hertford College, Oxford, he was called to the Bar by Gray's Inn in 1958 and was a tenant at Blackstone Chambers from 1983 until his death on 3 January 2010.
During his academic career he taught at the University of Leeds, the University of Nottingham, and Wadham College, Oxford (where he was a Fellow). He was a professor of international law at the London School of Economics between 1976 and 1980. From 1980 to 1999, he was Chichele Professor of Public International Law and a Fellow of All Souls College at the University of Oxford; he was appointed a Distinguished Fellow of All Souls in 2004.
He served as an advisor to United States President Jimmy Carter during the 1979 Iranian Hostage Crisis. The cases in which he argued before the International Court of Justice include Nicaragua v. United States, Nauru v. Australia, Bosnia and Herzegovina v. Serbia and Montenegro, the Pedra Branca dispute, Libya v. United Kingdom, Libya v. United States, and Democratic Republic of the Congo v. Uganda. He also argued several important cases before the European Court of Human Rights, including Cyprus v. Turkey. He also represented Amnesty International at the extradition trial of Chilean coup-leader Augusto Pinochet before the English courts in 1999. He was a member of the United Nations' International Law Commission from 1997 until his resignation in 2008. Brownlie was a Fellow of the British Academy and his memberships included the International Law Association and the Institut de Droit International. In 2006, he was awarded the Wolfgang Friedmann Memorial Award for international law. He was knighted in the 2009 Birthday Honours. Brownlie died in a car accident in Cairo on 3 January 2010.