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Expert Profile

Mark Castell

Mark Castell

Regional Head of Diales (Europe, Middle East) - Quantum and Delay Expert



Memberships & Associations

Fellow of the RICS
Associate of the CIArb

Contract Experience

UAV dutch

Presentations & Training

Over 100 training courses on subjects including commercial awareness, management of contracts, claims management, risk management and FIDIC.
Speaker at CIArb Netherlands chapter meetings and CIArb European branch conference.
Guest speaker at various conferences.


Oil & Gas
Process & Industrial

Regional Experience

Asia Pacific
Middle East
United Kingdom

Cross-Examination Experience



  • Chartered Quantity Surveyor
  • Over 30 years of construction contracts and dispute experience
  • Extensive domestic and international arbitration and litigation experience
  • Numerous expert appointments including ‘hot tubbing’ experience (witness conferencing) experience
  • Appointed to undertake expert determination
  • Can communicate in Dutch and French languages


Mark trained as a quantity surveyor working for large contracting organisations in the UK principally working on civil engineering projects with an increasing involvement in disputed contractual matters, claims, delays and formal dispute proceedings.

After a period working in France, Mark moved to contract and commercial consultancy in 1999 and then relocated to the Netherlands in 2003. His experience then broadened with involvement in projects in the building, energy, infrastructure, marine and offshore; and process and industrial sectors in Europe (including Belgium, Bulgaria, France, Germany, Luxembourg, the Netherlands, Norway, Poland, Portugal, Romania and the UK), Africa (including Egypt, Gambia, Libya, Kenya and Nigeria) the Far East, the Middle East (Iraq, UAE and Oman), USA and the Caribbean.

Mark has been appointed as expert witness more than 25 times on quantum and delay matters covering the effects of re-measurement; variations / changes to work scope; disruption; delays and extensions to completion dates; acceleration and claims related to defects and incomplete work. These appointments have concerned disputes of more than $110 million and several years of delay. He has given both written and oral evidence to tribunals and courts, has experience of witness conferencing and has been cross examined by counsel on a number of occasions in international arbitration proceedings.

Mark has also undertaken binding expert determination (in Europe and the Middle East) and has been a court- appointed expert (in the Netherlands) on both quantum and delay matters.

Mark can communicate in the Dutch and French languages.

This expert has the following cross-examination experience:

  • International Arbitration
  • Domestic Arbitration
  • Adjudication/Mediation
  • Crown Court

This expert has been recently instructed by:

  • CMS Cameron McKenna
  • Egyptian Media Production Company / Kosheri, Rashad & Riad
  • European Investment Bank/Holland van Gijzen Advocaten
  • Eversheds-Sutherland
  • Fenwick Elliott
  • GDDKiA / Clifford Chance
  • Gide Loyrette Nouel
  • IREM / Coccia De Angelis Pardo & Associati
  • Popovici Nitu & Asociatii
  • Ministry of Transport and Communications – Sultanate of Oman
  • Severijn Hulshof Advocaten
  • White & Case
  • Vinson & Elkins

“We have been impressed by the professionalism, rigorousness, experience and the independent and impartial judgment of Mr. Mark Castell, as well as his knowledge and familiarity with the arbitral proceedings. We will thus recommend Mr. Mark Castell wholeheartedly for similar proceedings.”