Keith Hamilton is an historian in the Foreign and Commonwealth Office. His most recent publication (co-edited with Patrick Salmon) is Slavery, Diplomacy and Empire: Britain and the Suppression of the Slave Trade, 1807-1975 (2009).Richard Langhorne is Professor of Global Politics at the University of Buckingham and a Full Professor in the Division of Global Affairs at Rutgers University, USA. He was formerly Director of Wilton Park, FCO, (1993-1996) and Director of the Centre of International Studies at Cambridge University (1987-1993).