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Expert Profile

Leslie Harland

Leslie Harland

Quantum Expert

MSc Construction Management
REDAS (Sing)
SIAS (Sing)
Oil & Gas
Process & Industrial
Asia Pacific
Middle East


  • Chartered Quantity Surveyor
  • Over 35 years’ industry experience
  • Worked throughout  UK, Europe, and Asia Pacific
  • Extensive experience in the valuation of damages claims
  • Party appointed Quantum Expert on disputes up to USD 500M
  • Cross-examined in various legal jurisdictions and in virtual hearings


Leslie is a Chartered Quantity Surveyor and Chartered Civil Engineering Surveyor with over 35 years’ experience in the construction and engineering industry, having held several senior management appointments in major contracting organisations and contract advisory consultancies in the UK, France and Singapore.

In the early part of his career, Leslie trained in the UK with a firm of professional quantity surveyor’s and then a main contractor. His core competencies include quantity surveying, commercial management and contract administration. Notable UK projects worked by Leslie include the Thames Barrier and Enron Power Station located at Teesside.

In the middle to latter part of his career, Leslie has focused on dispute avoidance, having advised clients on various construction and engineering related matters including liability for disputed extra work, rating of variations, resolving problematic final accounts, claims for unforeseen ground conditions, valuation of defective construction work, payment for accelerated working and prolongation costs. More recently, Leslie has provided advice on time and cost entitlements under the Singapore standard forms of contract due to the outbreak of the Covid-19 pandemic.

Leslie has significant industry sector experience, which includes; commercial developments & educational facilities, oil & gas (Rigs, FPSO’s and sub-sea mining), airports, pharmaceutical plants, power stations (sub & supercritical) including coal, oil, gas fired and biofuel and desalination plants, roads, bridges & rail networks (above & below ground). This involved Leslie working on a variety of project delivery methods, including Alliancing, PPP, D&B, EPC, GMP and Traditional, operated under various forms contract.

Leslie has assisted project sponsors, insurers, and contractors in multimillion-dollar construction disputes and has been instructed on numerous occasions as a party appointed Expert Witness on complex quantum related issues (Building, Civil and M&E installations) on large capital infrastructure projects across APAC, Middle East and South Africa. Leslie has prepared expert reports, reply reports and joint reports and has testified in various legal jurisdictions, including the USA, South Africa, UK, Republic of South Korea and Singapore. More recently, Leslie testified in two virtual arbitration hearings (ICSID and DIFC-LCIA rules) seated in Washington DC and Dubai.

This expert has the following cross-examination experience:

  • Adjudication/Mediation
  • International Arbitration
  • High Court

This expert has recently been instructed by:

  • Addleshaw Goddard LLP
  • Baker Botts LLP