Sinclair grew up in London and Norfolk and was educated at Gresham's School[1] and the University of Oxford, where he gained his BA and doctorate.

[5] Sinclair published widely on a range of topics in economics,[6] including the optimal rate of inflation, central bank independence, the costs and benefits of monetary union, and international trade policy.

Sinclair maintained a connection with the Bank of England after leaving CCBS in 2008, including as a visiting academic, advising on research and teaching graduate entrants for many years.

[8] He was the author of numerous articles and books on economics, one written with his first wife,[9] the late economist Shelagh Heffernan, who was Professor of Banking and Finance at the Cass Business School, City University London.

[11] Others include King Letsie III, Camilla Cavendish, Peter Conradi, Diane Coyle, Tim Harford, Lieutenant General Michelle D. Johnson, Dave Ramsden, Guy Spier,[12] Abhisit Vejjajiva and a prominent Nepali economist and Asia Times opinion writer Bhim Bhurtel, Ross Bailey and Anthony Brown.