Since joining the Department at Reading, Professor Duff has held visiting professorships and research fellowships at Shanghai University (2016), Princeton University's Seeger Center for Hellenic Studies (2016), the Freie Universität Berlin (2007–9, awarded by the Alexander von Humboldt Foundation), the Australian National University (2006), Wolfson College, Cambridge (2005), Harvard University's Center for Hellenic Studies (2004), and the University of Cincinnati (2002). He has also taught at the British School at Athens (2002). In 1999–2000 he held a UK Arts and Humanities Research Council (AHRC) Research Leave award, also at the British School at Athens.
He is a Senior Member of Wolfson College, Cambridge, and a Fellow of the Royal Historical Society.
In addition to his role in the Department of Classics, he is also the Director of the Centre for Hellenic Studies and Coordinator of Modern Greek in the Department of Languages and Cultures.