Lewis Van Emden BSc (Hons) ACA -

Managing director

Lewis has been Managing Director of O’Brien & Partners for 8 years. Gaining his professional qualifications with Deloittes, based in London, and developing his experience at national practices. He brings over 30 years of expertise in areas such as business development and commercial advice including profit improvement and succession. Lewis continues to maintain strong relationships with long standing clients at O’Brien & Partners and is no stranger to the Welsh business market.


Mark Aherne CTA -

Tax Director

Mark gained his professional qualifications at Deloitte & Touche before moving to a regional firm to focus on owner managed businesses. He then joined the Cardiff Office of national practice PKF where he was promoted to senior manager and gained significant experience in areas such as mergers & acquisitions, company reconstructions, employment issues, property transactions, profit extraction, research and development and many other complex planning matters. Mark heads up the tax department at O’Brien & Partners and brings over 18 years experience with him.


Gareth Francis FCCA – Director

Gareth joined O’Brien and Partners in July 2012 having qualified in 1998 with Deloitte, Cardiff. He has over 30 years audit and accounting experience. This experience has been gained through a range of assignments, both locally and internationally.


O’brien & Partners - Chartered Accountants & Registered Auditors.
Member of The Institiute of Chartered Accountants in England and Wales Registered to carry on audit work in the UK and Ireland and regulated for a range of investment business activities by the Institute of Chartered Accountants in England and Wales.

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Details of our professional indemnity insurer’s agent is Aqueous Management Limited trading as Aqueous Underwriting (Registered in England under company 11453265) Registered at 5th Floor, Marlow House, 1A Lloyd’s Avenue, London, ECN 3AA.The territorial coverage is worldwide excluding professional business carried out from an office in the United States of America or Canada.


Our offices are based in Treforest and Cwmbran (see contact page for further details). 


O’Brien & Partners and Griffith Green Arnold are trading names of O'Brien & Partners KVE Ltd.

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