John Mastoras

John Mastoras is a senior partner in our Canadian employment and labour law group, and acts exclusively for employers. He is known to clients as a passionate and dedicated labour lawyer. He regularly litigates and provides strategic advice in connection with labour arbitrations, labour relations board disputes, collective bargaining negotiations, human rights proceedings, occupational health and safety charges, workplace insurance, labour injunctions and common law employment actions. His practice spans union and non-union workplaces for both federally and provincially regulated employers.

John is often chief spokesperson in collective bargaining and provides helpful counsel in this regard to a variety of employers. He also routinely acts for a number of employer associations and provides innovative and practical advice to the associations and their members.

John is frequently called upon to litigate highly contentious matters such as disruptive labour disputes and workplace mental health issues in various industries, including energy, pulp and paper, pharmaceutical, health care, insurance, long-shoring, retail, food processing, transportation, steel, building services, technology, automotive and manufacturing more generally.

John has taught for a number of years at the University of Toronto's Centre for Industrial Relations and Human Resources (CIRHR), where he is an adjunct professor. He was conferred the Morley Gunderson Prize by the University of Toronto as a CIRHR graduate who combines outstanding professional achievement with significant service to the university.