Roger Isaacs is an award-winning, highly experienced and widely respected Forensic Accountant, expert witness and licensed insolvency practitioner in the UK. He is a fellow of the Institute of Chartered Accountants in England and Wales (ICAEW).

In 2010, he became one of the first accountants in the country to be accredited by the ICAEW as both a forensic accountant and expert witness, recognition that reflected his expertise across divorce, shareholder disputes, fraud investigations and loss of earnings claims.

He is accredited by the Academy of Experts to provide Expert Determinations and sits on the appointment panel of the President of the ICAEW as an expert determinator, underlining his standing in complex financial disputes.

As National Technical Director of the Network of Independent Forensic Accountants (NIFA), Roger has given evidence in several hundred cases, providing expert testimony in written reports and under cross-examination before the High Court as well as in more unusual tribunals such as the International Court of Arbitration, the Lands Tribunal, the County Court and Employment Tribunals. He has provided concurrent evidence several times in what is known as “hot-tubbing”.

He led a team of forensic experts that helped to secure millions of pounds for subpostmasters and subpostmistresses, following the Post Office Horizon IT Scandal, for which he was named Practice Leader of the Year at the 2025 Accounting Excellence Awards.

Beyond the realm of forensic accounting, Roger was appointed to be the Global Chair of MGI Worldwide, an international accountancy network, then ranked amongst the Top Twenty in the World. In that role he oversaw MGI’s merger with the CPA Associates network and introduced an International Youth Shadow Board to help harvest the talent and perspectives of the next generation of accountants.

Roger has particular expertise in the following matters:

• Valuing shares and businesses in matrimonial, partnership and shareholder disputes
• Insolvency-related litigation
• Commercial agency disputes
• Commercial and contractual disputes
• Fraud and criminal cases
• Expert determinations
• Asset tracing
• Complex numerical analysis
• International and cross-border disputes
• Advising on liability and quantum in accountancy professional negligence cases for both claimant and defendant
• Quantifying the loss of earnings resulting from personal injury, medical negligence and other cases
• Assisting in the calculation of dependency claims in fatal accident cases
• Damages claims and claims for business interruption

Alongside his forensic practice, Roger has extensive experience as a licensed insolvency practitioner, having advised businesses in financial difficulty and acted as liquidator in both solvent and tax-driven reorganisations.
He also lectures widely on topics including business valuation, directors’ duties and strategic planning, and is a prolific writer whose articles appear in the technical press and national media. He sits on the editorial board of the Family Remedies Journal.

Regularly called upon by the BBC and national newspapers, he has also appeared on national TV and radio and lectured at the Shrivenham Defence Academy.

In addition to these roles, Roger is a CEDR-accredited civil and commercial mediator and Fellow of the Civil Mediation Council, combining his financial and valuation expertise with impartial facilitation skills to help parties resolve disputes more efficiently and cost-effectively.