Thomas Diez is Professor of Political Science and International Relations at the University of Tübingen.

He received his PhD from the University of Mannheim and worked as a staff member at the Copenhagen Peace Research Institute COPRI from 1997 to 2000. In 2000, he was initially appointed Lecturer at the University of Birmingham, where he was promoted to Senior Lecturer in 2003 and Professor in 2005. He has been in Tübingen since April 2009. He has also taught at universities in Aarhus, Copenhagen, Munich, and Victoria (British Columbia). In September 2009, he received the Anna Lindh Prize for his contributions to the study of EU foreign policy. He served as president of the European International Studies Association from 2015 to 2017.

Among his major publications are The EU and Global Climate Justice: Normative Power Caught in Normative Battles (co-author, Routledge 2021), The EU, Promoting Regional Integration, and Conflict Resolution (co-editor, Palgrave 2017), The Securitization of Climate Change (co-author, Palgrave, 2016), A Different Kind of Power? The EU's Role in International Politics (editor, International Debate Education Association / Central European University Press 2014), European Integration Theory (co-editor, 2nd edition Oxford University Press 2009), and Cyprus: A Conflict at the Crossroads (co-editor, Manchester University Press 2009). He is also the author of numerous international journal articles and managing editor of the Nomos series "International Relations" on behalf of the DVPW Section on International Relations.