During his 14-year career at DuPont, Gregory helped develop process to partially oxidize n-butane to maleic anhydride. At the commercial plant in Spain, his design modification increased yield and thus annual revenues by $24 million (2000). He headed the fiber technology laboratory in Switzerland (2004). Now a Canada Research Chair at Polytechnique Montréal, he has trained over 250 people, seven of whom have become professors. He has also consulted for dozens of startups and multinational corporations. With his students, he has participated in the commercialization of eight technologies. The Ordre des ingénieurs du Québec awarded Gregory the Honoris Genius – Social Engagement Award (2022); the University of Calgary selected him for the Schulich Technical Achievement Alumni Award (2020); he was elected a Fellow of the CIC (2023) and of the Canadian Academy of Engineering (2025).