Matthew L.O. Certosimo

C.S.

Partner

Toronto
MCertosimo@blg.com
416.367.6068

Matthew is certified by the Law Society of Ontario as a Specialist in Labour Law. He represents employers in labour and employment-related litigation, including wrongful dismissals and labour arbitration. He frequently appears before the courts, including at the appellate level.

He also acts for employers in grievance arbitrations, matters before the Labour Relations Board, and in collective bargaining.

And he represents employers, supervisors and constructors in proceedings under the Occupational Health and Safety Act, including in defence of quasi-criminal charges further to workplace accidents and injuries.

Matthew acts for and advises private and public sector employers on a full range of labour and employment matters, including:

  • dismissals and discipline
  • employment contracts and policies
  • human rights issues, such as discrimination and harassment
  • workers' compensation, employment standards, and occupational health and safety matters

Matthew is the co-author of Just Cause: The Law of Summary Dismissal in Canada, which is frequently cited in decisions. 

Within BLG, Matthew held the role of National Leader of BLG’s Labour & Employment Group from 2011-2016, and before that was the Toronto Leader from 2008-2011.

Matthew is certified by the Law Society of Ontario as a Specialist in Labour Law (which includes employment law), and he has held this Certified Specialist designation since 2011. Matt is the recipient of the Ontario Bar Association Randall Echlin Award for Excellence in Labour and Employment Law (2022).

He represents employers in labour and employment-related litigation, including wrongful dismissals and labour arbitration. He frequently appears before the courts, including at the appellate level.

Testimonials

Experience

  • Acts on behalf of employers and employees in employment-related litigation, including wrongful dismissals.
  • Acts on behalf of employers in grievance arbitrations, matters before the Labour Relations Board, and in collective bargaining.
  • Acts on behalf of employers, supervisors and constructors in proceedings under the Occupational Health and Safety Act, including in defence of quasi-criminal charges further to workplace accidents and injuries.
  • Advises private and public sector employers in full range of labour relations and employment law matters, including: dismissals and discipline; employment contracts and policies; human rights issues, i.e., discrimination and harassment; workers' compensation, employment standards and occupational health and safety matters.

Beyond Our Walls

Professional Involvement

  • Member of the Canadian Bar Association (Ontario)
  • Member of the American Bar Association
  • Past member, Board of Governors, Wilfrid Laurier University
  • Past member, Justices of the Peace Appointments Advisory Committee, Ministry of the Attorney General (Ontario)

Awards & Recognitions

  • Recognized in the 2025 edition (and since 2010) of The Best Lawyers in Canada® (Labour and Employment Law).
  • Recognized in the 2025 edition (and since 2016) of Chambers Canada — Canada's Leading Lawyers for Business (Employment & Labour: Ontario) and in the 2020 edition (Employment & Labour: Nationwide).
    • Excels in representing employers across both the public and private sectors…He continues to represent major national clients in the full gamut of labour and employment matters. He is also adept at grievance arbitrations and collective bargaining.
  • Recognized in the 2024 edition (and since 2009) of Lexpert®/American Lawyer Guide to the Leading 500 Lawyers in Canada (Employment Law).
  • Recognized in the 2024 edition (and since 2007) of The Canadian Legal Lexpert® Directory (Employment Law, Labour Relations) and the 2024, 2021 editions (and since 2007) for (Workers' Compensation, Workplace Human Rights).
  • Recognized in the 2024 edition (and since 2022) of Who's Who Legal: Canada (Labour, Employment & Benefits). He is also recognized in the 2024 edition as "Global Elite Thought Leader: Labour & Employment" and "Thought Leaders - Labour & Employment"
  • Recognized as a 2023 Thomson Reuters Stand-out Lawyer
  • Recognized in the 2023 edition (and since 2015) of Legal 500 Canada as a Leading individual (Labour & Employment).
  • Recipient of the Ontario Bar Association Randall Echlin Award for Excellence in Labour and Employment Law for 2022 (Awarded in March, 2023)
  • Recognized in the 2019 edition (and since 2016) of Benchmark Canada - The Definitive Guide to Canada's Leading Litigation Firms & Attorneys as a "Local Litigation Star: Ontario" and a "Litigation Star: Labour and Employment."

Bar Admission & Education

  • Ontario, 1995
  • LLB, Dalhousie University, 1993
  • BA (Hons.), Wilfrid Laurier University, 1988