During his time at Laurier, Marc Kilgour has benefited from several sabbatical and other leaves, and was usually able to spend time with research colleagues. He has held visiting positions at University of Vienna, Austria; Tottori University and Kyoto University, Japan; Nanjing University of Aeronautics and Astronautics, China; University of Sydney, Australia; Université de Caen and Ecole Normale Supérieure de Cachan, France; Graduate Institute for International Studies, Switzerland; and University of Waterloo.
Marc Kilgour is a mathematician whose expertise lies primarily in the application of mathematical ideas and principles to other fields. Most of these applications involve decisions in some way, usually group decisions or decisions by individuals within a group. The objective may be:

normative – to find the “optimal” decision;
descriptive – to model the world as it is;
prescriptive – to finding the best decision for a particular decision-maker, based on his or her view of the situation; or
structural – to design a framework that facilitates good (or better) decisions.
Marc Kilgour has approximately 400 refereed or edited publications, including over 200 articles in refereed journals.

Marc Kilgour sees his research as lying at the intersection of mathematics, engineering, and social science. He has contributed on a wide range of topics including arms control, environmental management, negotiation, arbitration, voting systems, fair division, and coalition formation. As well, he has co-developed several decision support systems for strategic conflict.