Alexandra Sidossis is dually-qualified as a barrister in England and Wales and as a New York attorney, and is a qualified commercial mediator and a Member of the Chartered Institute of Arbitrators (MCIarb).

Alexandra’s practice focuses on commercial law, and particularly employment law and international arbitration.


In her employment practice, Alexandra has represented both Claimants and Respondents in the Employment Tribunal, in multi-day unfair dismissal, discrimination, TUPE and whistleblowing cases. Often, she is successful in reaching favourable settlements for her clients. Notable cases include:

  • Mr Costagliola di Fiore and Ms Qadri v Introhive – Instructed on behalf of the Claimants in this multi-day claim for detriment and dismissal due to whistleblowing (led). The case is currently being appealed. 
  • Mr A Draper and ors v Canute Haulage Group Limited & 7 ors: Instructed on behalf of eight Claimants against eight Respondents in this TUPE matter, in a seven-day preliminary hearing and to advise. The ET found that a transfer had occurred to one of the respondents.
  • Mr S Dubarry v Sainsburys Supermarket Ltd: Instructed on behalf of the Claimant at the final hearing, which took place over five days, in this claim for unfair dismissal and disability discrimination. The claim was successful.
  • Confidential claim against an equity research company: Instructed, direct access, to advise and settle the pleadings by the claimant, ex-CFO of an equity research company, in her claim for detriment and dismissal following protected disclosures. The matter settled prior to the preliminary hearing, resulting in a six-figure settlement.
  • Confidential claim against a local authority : Instructed by the Claimant, direct access, in his claim for detriment and dismissal due to whistleblowing.
  • Ms Siobhan Cafferkey v (1) Allied Healthcare (2) Quality of Life Homecare Ltd (3) London Borough of Brent: Instructed on behalf of the Claimant to represent her in this two-day TUPE claim. She was successful in proving that her employment had transferred from the first to the second respondent.
  • Eduardo Alexandre Grazioli v Charles Gregor Solicitors Ltd: Instructed on behalf of the Respondent to settle the pleadings in this claim of constructive unfair dismissal, whistleblowing and unlawful deduction of wages.

Alexandra also has extensive experience and expertise in advising employers and employees in all matters of employment law, contentious and non-contentious, including disciplinary, capability and redundancy processes.

Alexandra is instructed as a sole and junior counsel in commercial ad-hoc and institutional arbitrations, including instructions to advise by reference to English and/or New York State law in international matters. Notable matters include:

  • Confidential: Instructed to advise on challenging an arbitration award rendered under the Swiss Rules of International Arbitration (led by Richard Samuel). 
  • Confidential: Instructed by the Claimant to advise in this matter for contractual debt of approximately £1m, and settle the ICC request.
  • Confidential: Instructed by a foreign law firm to settle an arbitrator’s note on English law, in a dispute relating to a Facility Agreement, involving US a conflict between English and USA law (led).
  • Confidential: Instructed to advise on the validity of an arbitration clause in a transport claim.
  • Confidential: Instructed to advise and settle claim submissions in a LMAA arbitration regarding damaged goods (amount of claim just over $500,000).
  • Confidential: Instructed by a sovereign to advise on a potential arbitration claim for damages in relation to historic land contracts (led).

Alexandra accepts instructions in a wide ambit of commercial matters, as sole or led Counsel. Her experience includes advice, settling of pleadings and representation in commercial cases, often with a cross-border element. Notable cases include:

  • Instructed to advise on, and settle Particulars of Claim in, a contractual dispute relating to the interpretation of a payment clause. 
  • Confidential: instructed to advise and settle particulars of claim in a dispute against a security company regarding the theft of goods.
  • Confidential: Instructed to advise on the tax consequences which the executors of an estate could be exposed to if the third beneficiary’s estate disclaims his inheritance under the laws of New York.
  • Confidential: Instructed to advise on the validity of commercial contracts, and whether the defendant in this matter had a basis for rescission.

Alexandra is able to accept instructions directly from members of the public, companies and other entities through the public access scheme (also known as direct access).  She is able to advise and draft pleadings and documents for individuals and small and medium sized businesses on a direct access basis. She is happy to accept instructions on a direct basis in appropriate cases. If you wish to instruct Alexandra on a direct basis, please speak to the practice managers.

For more information on public access, please see the Bar Council website.

For Help or Advice…

Please contact us either by telephone: +44 (0)20 7415 7800 or email:

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