Les O'Connor is a senior litigation lawyer specializing in mediation and arbitration. He has been involved in all facets of construction related work for over 35 years.

He has appeared in all levels of court in Ontario, trial and appellate, including the Supreme Court of Canada. His practice deals with issues relating to construction liens, from the claimant and defence perspectives, advising clients such as municipalities and private industry contractors and owners about construction contracts, tendering and RFP issues, bond and insurance claims, delay claims and other construction associated issues.

Les’s past cases have included lengthy trials concerning liens on the Hamilton Sewage Treatment Plant, runway construction at the Mount Hope Airport, and, more recently, Bad Concrete in housing developments in the G.T.A.

Les is a fully trained Mediator and Arbitrator. He has taught in the Bar Admission Course on Advocacy for a number of years and is past Vice chair of the Civil Litigation Section of the Ontario Bar Association. He is a member, director and former president of the ADR Institute of Ontario (ADRIO) and active in both its Construction and Employment Sections. He has recently taught seminar courses in Construction Law for both the Ontario General Contractors Association (O.G.C.A.) and George Brown College.


    • Repeatedly recognized by Best Lawyers in Canada as a leading lawyer in Construction Law
    Called to the Bar
    • Ontario (1974)

    • LL.B., University of Toronto, 1972
    • B.A., University of Toronto, 1969
    • Ontario Bar Association (Civil Litigation Section)
    • Metropolitan Toronto Lawyers Association
    • ADR Institute of Ontario
    • Thomas More Lawyers' Guild

    Speaking Engagements

    Speaker, "Punitive Damages", WeirFoulds Employment & Labour Law Group Client Seminar, Toronto, ON, April 6, 2017

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    Legend: GeneralLitigationPropertyCorporateGovernment

    Legend: GeneralLitigationPropertyCorporateGovernment