Search Site

Our Team

Leslie Dizgun

Co-Chair, Business Litigation Group

Leslie Dizgun conducts a sophisticated commercial litigation and employment law practice.  Mr. Dizgun is often retained by other employment law lawyers and family law lawyers on commercial litigation issues arising in their practice areas.

In addition to his litigation practice, Mr. Dizgun is a well respected mediator and arbitrator of commercial and employment disputes. He is a member of the ADR Chambers expert panels. The ADR Chambers is the largest alternative dispute resolution service provider in the world. Mr. Dizgun has been very successful in resolving difficult and complex proceedings.

Mr. Dizgun has a Master of Laws degree in Alternative Dispute Resolution from  Osgoode Hall Law School, where he is also an adjunct professor. He has taught Civil Procedure, the Senior Colloquium in Dispute Resolution and the Administration of Justice, and continues to teach Dispute Settlement in the Civil Justice System.

Mr. Dizgun is committed to standards of excellence in advocacy and dispute resolution.  He is often asked to teach and instruct other lawyers in continuing education programs. He was recently honoured by the Advocates Society, the premier advocacy organization for litigation lawyers, with the award for teaching excellence, for his contributions to the continuing legal education of lawyers in Ontario.

Mr. Dizgun brings a sophisticated and nuanced approach to representing clients, and has the skills and experience to achieve excellent results in an efficient and cost effective fashion.


Best Lawyers

Leslie Dizgun is an experienced mediator and arbitrator. In addition to his private practice in civil litigation and employment law, he is a Chartered Mediator. Mr. Dizgun’s dispute resolution practice includes the mediation and arbitration of contract, business, libel, wrongful dismissal, workplace, franchise, real estate and construction matters. Mr. Dizgun has successfully mediated and arbitrated numerous commercial disputes. Mr. Dizgun is an adjunct professor of Osgoode Hall Law School at York University, where he has taught Civil Procedure, the capstone colloquium in Litigation, Dispute Resolution and the Administration of Justice, and currently teaches Dispute Settlement in the Civil Justice System. Mr. Dizgun is a frequent speaker and instructor on ADR and Dispute Resolution topics. He has also recently been awarded the Advocates Society Award For Excellence In Teaching.


  • 30 years’ experience in dispute resolution
  • Mediated many commercial contract, wrongful dismissal and related disputes as a mediator with the Ontario Court ADR Centre Pilot Program and as a Toronto Roster Mediator
  • Acted as trainer for the Office of the Attorney General, training government lawyers in mediation techniques and mediation advocacy
  • Acted as a coach for the National Judicial Institute in settlement conference training for judges and masters
  • Panel Member: Ministry of the Attorney-General Orientation for Roster Mediators
  • Participated in numerous mediations in both the public and private sector as counsel, including the resolution by way of mediation and arbitration of a large class action suit
  • Sole mediator: Pilot Program, Royal College of Dental Surgeons. Mediation of professional misconduct complaints
  • Has mediated numerous disputes to a successful resolution
  • Has arbitrated corporate/commercial, contract, franchise, condominium, real estate, and employment disputes
  • Past Vice-Chair, Health Services Appeal and Review Board
  • Med/Arb: Crossing the Line, in a Practitioner’s Guide to Commercial Arbitration, ed. Michael Silver, 2017.
  • Co-Chair, Employment Litigation Advocacy, Advocates Society, 2018.
  • Co-Chair, Advanced Mediation Advocacy Workshop, Advocates Society, 2017.
  • Mediation Advocacy, in Mediation and Negotiation: Representing Clients, ed. M. Silver, 2001.
  • 14 th Annual Employment Law Summit: Panel Presentation, The Psychological Aspects of Negotiation: October 22, 2013
  • Co-Chair Mediation Advocacy Workshop, Toronto, London, Halifax, St. Johns Newfoundland, and Ottawa, Advocates Society, 2011, 2012, 2013, 2014, 2015, 2016, 2017.
  • Co-chair, ADR Workshop: Creative and Efficient Use of ADR in Franchising, 2012 OBA Franchise Law Conference
  • Co-chair, Arbitration Workshop: Does A Decision To Arbitrate Still Make Sense, 2011 OBA Franchise Law Conference.
  • Employment Law Summit 2010, Presentation: Torts in the Workplace after Piresferreira and Bill 168, LSUC, October 28, 2010.
  • Canadian Institute: 6 th Annual Advanced Forum on Employment Law – Presentation: The Elusive [Un]Certainties of Employment Law. October 18 th and 19 th , 2006.
  • Faculty, Advocates Society of Ontario. Workshop instructor in Evidence, Expert Evidence, Cross-Examination, Trial Advocacy, Negotiation Skills, Labour and Employment Advocacy.
  • Co-author of Mediation Advocacy: Effective Client Representation
  • Co-chair, Mediation Advocacy Workshops, for BCCBA Branch Conference and Advocates’ Society, November 2010, November 2011(Toronto), April 18, 2012(London), and November, 2012 (Toronto)
  • Co-Chair of Conference on Alternative Dispute Resolution: Strategies to Resolve Workplace Conflict and Focus on Corporate Productivity, May 27 and May 28, 1999
  • Training Superior Court Judges in effective Settlement Conference Practices, National Judicial Institute, November/December 1999
  • Co-Chair of the Advocates’ Society/ Law Society of Upper Canada Civil Motions Workshop, 1999, 2002, 2003 and 2004, 2008, 2010
  • Training Superior Court Judges in effective Settlement Conference Practices, Advanced, National Judicial Institute, December 2000
  • Training Ontario Government lawyers on behalf of the Office of the Attorney General in Mediation Advocacy
  • Training Workshops in Mediation Advocacy for Torkin,Manes,Cohen & Arbus, Weir & Foulds, Gowlings, Norton Rose Fulbright, and McCarthy, Tetrault
  • Panel Member, January 1999 - The Ministry of the Attorney General’s Orientation of Mandatory Mediation Roster Mediators
  • Osgoode Hall Law School of York University, Professional Development Programme, November 3 & 4, 1998, Mandatory Mediation. Presentation: Choosing the Mediator - From the Roster; From Off the Roster
  • Insight Information Inc., June 19, 1998, Mandatory Mediation. Presentation: The Nuts and Bolts: A Walk Through the Rules
  • Presentation and paper on Mediation Advocacy. LSUC, February 10, 1998, Resolving Commercial Disputes. Presentation and Paper: Managing Multiple Claims: Expanding the ADR Arena
  • Presentation, CBAO Annual Institute, January 30, 1998, ADR Section Programme. Presentation and Paper: Mediation Advocacy
  • Faculty, Counsel in a Mediation, Ontario Centre for Advocacy Training, April, 1997
  • Panel Member, CBAO Seminar. Mediating in a Mandatory Regime. 1997

Bachelor of Arts, University of Toronto, 1973

Master of Arts, Concordia University, 1984

Bachelor of Laws (D. Jur.), Osgoode Hall Law School, York University, 1986

Certified Mediation Workshop, Harvard Law School, 1995

Master of Laws in Alternative Dispute Resolution, Osgoode Hall Law School, York University, 1997

Member, Advocates Society

Chartered Mediator, ADR Institute of Canada

Past Member, Transitional Physician Audit Panel of the Health Services Appeal and Review Board (2003-2006).

Past Vice-Chair, Health Services Appeal and Review Board (2006-2009)

Past board member, Osgoode Hall Alumni Association (2004-2010)

Past Member, Equal Pay Coalition

Past Board Member, Pay Equity Legal Clinic

Adjunct Professor, Osgoode Hall Law School