Jonathan Haydn-Williams

Senior Counsel

Jonathan is a Solicitor and Senior Counsel in the Goodman Derrick Dispute Resolution team. He has over 30 years experience of handling and resolving a wide range of civil and commercial disputes.

He trained and worked at Allen & Overy and was a partner with Taylor Wessing for several years. He is qualified as an Accredited Mediator, registered with the Civil Mediation Council.

Areas of Work

Jonathan has long experience of advising and handling disputes in a wide range of legal and business areas, for companies, corporations, partnerships (including LLPs), governments, overseas lawyers and individuals. As well as resolving numerous contract and other general commercial disputes, he has particular experience of disputes in the following areas:

Profiles of his work in those areas can either be accessed by clicking on the links in the list above or provided on request to him.

Jonathan's approach

“I try to resolve disputes in the quickest and most cost effective way, aiming for the best realistic outcome available. This involves:

  • Analysing the facts and law so as to be able to give frank legal advice, both initially and as the case progresses
  • Reviewing the financial viability of bringing or defending a claim, by balancing:
    • the costs, risks and possible outcomes;
    • the availability of insurance; and
    • different methods of billing and funding legal costs
  • Taking account of the client’s personal or business goals and needs
  • If possible, advancing the claim or defence in correspondence before court action or arbitration is commenced
  • Encouraging negotiation and (if that’s unsuccessful) mediation or another form of alternative dispute resolution (ADR)
  • If proceedings are commenced, pursuing or defending them in a strategic, determined and cost-effective way, whilst keeping the possibility of settlement under review”.


Jonathan represented me in a long and difficult dispute with a major financial institution. He was able to analyse and assess the merits of the case and provide a cogent strategy to take it forward to a successful conclusion. At all times Jonathan communicated the strengths and weaknesses of the case as it progressed and adapted quickly and proactively to any shift in the negotiation. In the concluding mediation, Jonathan excelled and acted with utmost credibility at all times, whilst proving himself adaptable to changes in the dynamic and remaining objective throughout”. (Client not named as the settlement agreement contains a confidentiality clause).

“I have been a client of Jonathan for the past 25 years. That in itself says more than enough. Jonathan’s intelligent analysis and occasional left field approach matches my own and that is the reason we work well together”. (David Haggie, founding partner of a successful financial PR business).

“Jonathan worked with me in a calm manner and explained everything in a very clear way. We encountered many hurdles, which he navigated with great skill. I would not hesitate in recommending him: he is the personification of a wonderful litigator”. (Client not named as the settlement agreement contains a confidentiality clause).

“When I was in practice as an Attorney, Jonathan was for many years an invaluable resource to me, an overseas lawyer, in relation to matters concerning the UK and English law. As a Judge, I valued his insight in relation to issues of law that we regularly discussed”. (Peter Williams QC, retired Court of Appeal Judge, Barbados).

“I found Jonathan to be a lawyer of formidable intellect and ability with excellent communication and negotiating skills, who was always prepared to go the extra distance required to meet the commercial expectations and requirements of clients”. (Alastair Cornforth, a partner of Jonathan’s in a previous law firm).


Jonathan has written many articles for legal publications, including the Journal of the Chartered Institute of Arbitrators and the Law Society’s Gazette and Civil Litigation Section. A selection of articles by him can be found at

Education and Memberships 

Cambridge University (MA in Law);

Accredited Mediator (Regent’s University, London);

Civil Mediation Council (Registered Mediator);

Association of London Welsh Lawyers;

Association of Partnership Practitioners;


City of London Club; 

Committee of the Law Society’s Civil Litigation Section (Chair).

Out of the Office

Jonathan lives in Richmond with his family. He maintains his ancestral links with South West Wales and supports Swansea AFC. He also follows Chelsea FC and was a season ticket holder at London Welsh RFC. When time allows, he reads, sketches and tries to improve his guitar technique. He supports several charities, including the Lord Edmund-Davies Legal Education Trust, The Teapot Trust and Myeloma UK.

Foreign Languages

French (good understanding; reasonable fluency).