Latest News:

Q&A with expert witness, Simon Braithwaite Meet our Interns in New York Data Centre Essentials: Design, Construction, and Operation of Data Centres for the Non-expert Diales host session at Berlin Dispute Resolution Days Diales collaborate to deliver another sculpture at the Goodwood Festival of Speed London Legal Walk 2023 We are delighted to release the third edition of the Diales Compendium Michelle McMillan is promoted to Director for Canada Combustibility & Liability – Who pays for the high rise fix? Diales welcomes a new Chief Financial Officer Driver Trett release their second Digital Digest Online Briefings | Cladding – The Implication For Valuation Meet and Greet Diales and EVRA in person Join our Technical support team in the Middle East Quantum Expert, Javier Sánchez Llopes, wins Client Choice Award Celebrating our first year in New York Get to know the new Regional Head of Diales in Oceania We are hiring in New York Diales Discusses – Virtual Hearings Diales staff are re-elected to the SCL Council Martin W. J. Smith, Diales Technical Expert, features in Big Project ME Diales launch new Middle East service: Arabic Litigation Support Diales welcomes Adrian Kong in Singapore Mark Wheeler, Head of Diales, to speak at the UK Adjudicators Conference Webinar: The role of Expert Witnesses in construction and engineering disputes Diales Technical collaborate with artist Gerry Judah, to create Drift. Diales open a new office in Madrid Diales announce collaboration with EVRA Consulting (PTY) Ltd (EVRA) Diales welcomes David Merritt to it’s team of experts Diales feature on Leaders League Diales open a new office in New York Diales Technical shortlisted in the British Construction Industry Awards 2020 Head of Diales, Mark Wheeler, is published in Lawyer Monthly. Chris Sunderland joins Diales as our Marketing and Business Development Director Diales Technical feature in photo contest Diales reception, 5th March 2020 COVID-19 UPDATE Diales Sponsor 8th ICC MENA Conference on International Arbitration Construction Claims Dubai – Record Keeping Evaluating Contract Claims, 3rd Edition – Out Now Diales are excited to sponsor the 17th ICC Miami Conference on International Arbitration Diales Sponsor the 7th Biennial Conference on Construction Projects from Conception to Completion How To Avoid Construction Disputes – Maria Fisentzou Diales nominated in Structural Awards 2019 Diales are delighted to announce that Phil Duggan been appointed as Head of Diales for the Middle East Diales are proud sponsors of Asia ADR Week 2019 Diales are pleased to be sponsoring the 5th ICC Asia Conference in Singapore Diales are pleased to be sponsoring the 4th ICC Africa Conference in Lagos this week Diales is proud to be sponsoring the 3rd PAW and to host a conference Diales is delighted to be taking part in the 3rd Kuwait Project Management Conference 2019. Diales is proud to be sponsoring the 7th ICC MENA Conference on International Arbitration Dealing with conflicting pressures – A practical guide Diales Technical are shortlisted for an award. Diales are proud sponsors of the CIArb’s International Arbitration Conference 2018 Flying high! Another Goodwood sculpture success Diales Host Drinks Reception GAR Live Construction Disputes ICC Institute Advanced Training on “Drafting enforceable awards” Should arbitration in investment protections treaties be forsaken? DRBF Conference – Paris, France Diales work with Gerry Judah on a new sculpture – Jacob’s Ladder Diales experts gain professional recognition Diales have two new experts Diales host successful drinks reception Diales are commended at the 2017 Structural Awards Mark Castell is attending the 2017 Dutch Arbitration Day, Amsterdam Independence Day: Why Do Many Experts Fail at Being ‘Independent’? John Mullen is published in the Construction Law Review Diales technical are shortlisted for two awards Diales celebrates five years of dedicated Expert Witness support services ICC 1st European International Arbitration Conference Diales are the lead sponsor of Kuala Lumpur International Arbitration Week

Expert Profile

Mark Stevenson

Mark Stevenson

Quantum Expert

Diploma in Surveying
Since 1999 Mark has delivered numerous and frequent presentations. He has also been writing and delivery training since 2014.
Oil & Gas
Process & Industrial
Middle East
United Kingdom


  • Chartered Quantity Surveyor
  • Chartered Civil Engineering Surveyor
  • 30 years’ experience in the engineering and construction industries
  • Extensive experience in the assessment of quantum


Mark is a Chartered Quantity Surveyor with 30 years’ experience in the engineering and construction industries. He specialises in dispute avoidance and resolution.

Mark has been appointed as a quantum expert in both litigation and adjudication proceedings on behalf of employers, contractors, sub-contractors, and consultants. Mark has also assisted the lead expert on many commissions. He has provided written reports in relation to the true value of works completed and losses incurred as well as providing opinion on the application of measurement rules.

Mark is experienced across a wide range of sectors including building, civil engineering, energy, infrastructure, oil and gas, process and industrial, and mining.

Prior to becoming a consultant Mark trained with Professional Quantity Surveying Practices and gained considerable experience in all aspects of pre and post-contract quantity surveying duties.

This expert has the following cross-examination experience:

  • Successfully completed external cross examination courses

This expert has recently been instructed by:

  • DAC Beachcroft
  • Kennedys Law
  • Paris Smith

“I consider XX was extremely fortunate to secure your services for this complex and delicate task, and I know the Trustees would wish me to pass on their thanks for all you have done for our charity … I would certainly have no hesitation in recommending you unreservedly.” (Institutional Employer)

“Your Report was excellent.  I used the two page summary in my presentation to Trustees today, and it was very useful to have independent corroboration of our views. The Trustees liked your recommendations, and we will be writing to … accordingly.  Thank you also for your suggestions as to how we can minimise the risks going forward.” (Institutional Employer, following report on mid-contract review) »