Guillaume obtained his LL.B. degree from the University of Montreal, graduating at the top of his class, and receiving more than ten awards for academic excellence, including the Faculty Medal for the highest standing in the LL.B. program. During his bachelor, he also served as a law clerk to the Honourable Justice Chantal Corriveau of the Superior Court of Québec and worked within a non-profit organization whose mission was to support and advise tenants with their legal inquiries.

Guillaume's primary field of interest is private international law. He is currently pursuing a first master of law degree at McGill University, for which he received the Hydro-Québec master's scholarship, awarded each year to an outstanding student from Quebec. Under the supervision of Professor Pierre-Emmanuel Moyse, he is writing a thesis on the interaction between virtuality and the development of private international law in the commercial area. In addition, he also works as an editor for the Revue québécoise de droit international.

Guillaume successfully completed the Québec Bar School program and works as a student-at-law at Heenan Blaikie since 2009, where he intends to complete his articling term.

While at the University of Cambridge, he will pursue courses in the fields of commercial law and private international law. Upon his return, Guillaume will serve as a law clerk to the Chief Justice of Canada, the Right Honourable Beverley McLachlin of the Supreme Court of Canada.