Guy Lefebvre is Emeritus Professor at the Faculty of Law of University of Montreal, where he served as a professor of international business transactions, business law and transportation law between 1988 and 2021. He continues to work as an Adjunct Professor. 

Recognized as an authority in the field of international business transactions law and the emergence of standards, he is the author of numerous books and articles published in several languages. Guy Lefebvre has founded  in 1997 of the Centre for Business and International Trade at the Faculty of Law,  His recognized expertise in business law and international education makes him a sought-after speaker on the national and international scene. He has been a visiting professor at several universities and regularly acts as an expert with international institutions.

Dean of the Faculty of Law from 2012 to 2014, after having long held the positions of vice-dean, he was part of the senior management of his University as vice-president of international affairs and Francophonie from 2014 to 2020. Guy Lefebvre has distinguished himself for more than thirty years by working tirelessly and with dedication to the development of international education and by highlighting Quebec's bijural system, all over the world.

Guy Lefebvre has also been involved in several major national and international councils, including the Board of Directors of the Observatory of Economic Francophonie, the Inter-American University Organization, the Canadian Bureau of International Education, the Franco-Quebec Council for University Cooperation and the Quebec Bar Foundation.

His countless contributions have earned him several awards and prizes both in Canada and abroad, including the Paul André-Crépeau Medal of the Canadian Bar Association  Guy Lefebvre is now a retired lawyer of the Quebec Bar, of which he is an emeritus lawyer (Ad. E.) and he is a distinguished member of the Quebec Order of Excellence in Education. 

Guy Lefebvre has studied at University of Montreal and University College London.