Gregory John Barrington Mills (born 9 May 1962)[1] heads the Brenthurst Foundation, based in Johannesburg, South Africa, established in 2005 by the Oppenheimers to strengthen African economic performance.
From 1996 to 2005 he served as the National Director of the South African Institute of International Affairs.
He is a visiting lecturer at the NATO Higher Defence College in Rome, and is a Fellow of the Royal Society of Arts.
During 2006, based in Kabul, he served as the special adviser to the Commander of NATO forces in Afghanistan, General Sir David Richards, and as the head of the strategic analysis Prism Group of the ninth International Security Assistance Force (ISAF IX).
These include: Mills is widely known for his proficiency on the penny whistle, accompanying musician Robin Auld on his song, "This Is How It Works.