Philippe Lagassé is Associate Professor and Barton Chair at the Norman Paterson School of International Affairs. His research interests include Canadian defence policy and procurement, Canadian defence governance and civil-military relations, and Canada-United States defence relations. His current research projects examine executive power and legislative-executive relations in Westminster states, with a particular focus on foreign and defence affairs.

Lagassé is the co-author of a forthcoming book on legislative oversight of military affairs and part of a new project examining defence ministries in a comparative perspective. His primary research project examines the idea of executive power in Canada, Australia, New Zealand, and the United Kingdom, through the prism of the royal prerogative. All three of these projects are funded by the Social Science and Humanities Research Council of Canada.

Lagassé has published widely in high-ranking academic journals and is the co-editor of Canadian Defence Policy in Theory and Practice, Volumes 1 & 2.

In addition to his academic work, Lagassé served as a member of the Independent Review Panel for Defence Acquisition (2015-2022) and as a member of the Independent Review Panel for the evaluation of options for the replacement of the CF-18 fighter aircraft (2012-2014).