Rueben obtained a Bachelor of Arts in Law (Honours) degree from the University of Kent at Canterbury, England in 1987 and a Master of Laws degree from the University of Malaya in 2002. He is a Barrister-At-Law, Lincoln’s Inn, London (admitted in 1989), a Barrister and Solicitor of the Supreme Court of the Australian Capital Territory and the High Court of Australia (admitted in 1990) and an Advocate and Solicitor of the High Court of Malaya (admitted in 1990). Rueben is also a Fellow of both the Chartered Institute of Arbitrators, United Kingdom (FCIArb.) and the Malaysian Institute of Arbitrators (FMIArb.), holds a Diploma in International Commercial Arbitration [DipICArb. (CIArb)] and a Certificate in Adjudication from the Kuala Lumpur Regional Centre for Arbitration (now known as Asian International Arbitration Centre (AIAC)).

Rueben was admitted to the Bar of England & Wales in 1989 by the Honourable Society of Lincoln’s Inn, London after which he returned to Malaysia to embark on his legal career. In December of the same year, he commenced his pupillage in the legal firm of Azman, Davidson & Co, Kuala Lumpur under the tutelage of his Master, Dato’ William Stanley Walker Davidson, an eminent lawyer and founding Senior Partner of that firm. Having successfully completed his pupillage, he was admitted as an Advocate & Solicitor of the High Court of Malaya in October 1990. Shortly thereafter, he was also admitted as a Barrister & Solicitor of the Supreme Court of the Australian Capital Territory and the High Court of Australia.

Upon his admission to the High Court of Malaya as an Advocate & Solicitor, Rueben was retained as an Associate in Azman Davidson & Co as of November 1990 and was later made a Partner in 1997. Having been with Azman Davidson & Co for 13 years, he then accepted the offer of partnership in Malaysia’s largest law firm at the time, Zaid Ibrahim & Co in February 2003. In May 2006, he ventured out to set up his own practice under the name and style of Rueben Williams. A year later, Rueben Williams merged with the firm of BH Lawrence & Co. and he remained there as a Partner in the firm’s Litigation Division until the end of May 2009 when he reverted to the former Rueben Williams on 1^st June 2009. In June of 2014, Rueben accepted the invitation to become a Partner in TH Liew & Partners (subsequently known as Zaid Ibrahim Suflan TH Liew & Partners) and continued practising there until its dissolution in August of 2026.

On 25 February 2010, Rueben was appointed a Notary Public by the Attorney-General of Malaysia.

Rueben has 36 years of litigation experience often acting in matters involving general civil litigation, defamation, insurance, contractual disputes, arbitration, construction, debt collection, landlord and tenant, employment law, and in the past for regulatory authorities like Labuan FSA (Labuan Financial Services Authority). He has appeared before the courts at all levels in Malaysia and has represented and acted for many prominent individuals and large corporations in a wide range of disputes.

In defamation actions, some of Rueben’s clients comprise companies and personalities such as Media Prima Berhad, New Straits Times Press (M) Berhad,  Metropolitan TV Sdn Bhd, Star Media Group, Free Malaysia Today (FMT), Tan Sri AK Nathan (Eversendai Group Chairman), Tan Sri Apandi Ali (former Attorney-General of Malaysia), Datin Paduka Chew Mei Fun (former Deputy Minister for Women, Family and Community Development & MCA Wanita Chief), actresses Sofea Jane Hisham and Amelia Henderson, former Director of the Asian International Arbitration Centre (AIAC), Dato Sundra Rajoo Nadarajah and former chairman of Bursa Malaysia Berhad, Datuk Shireen Ann Muhiudeen. Rueben was also a part of the team which acted for the former Prime Minister of Malaysia, Dato’ Sri Mohd Najib Hj Abdul Razak, in his application to adduce further evidence before the Federal Court.

Rueben has in addition, acted as Counsel for several law firms throughout his legal career, and in arbitration, he has appeared both as Counsel and presided as an Arbitrator in arbitration proceedings. At present, Rueben is an Arbitrator and Adjudicator on the panel of the Asian International Arbitration Centre (AIAC).

Rueben has previously served on the Bar Council’s Industrial Court Rules and Practice Sub-Committee, Kuala Lumpur Bar Committee’s Public Relations Sub-Committee and as an Examiner of the Malaysian Bar’s Ethics & Professional Conduct Written Examination. Rueben was also a Committee Member of the Chartered Institute of Arbitrators (United Kingdom) Malaysia Branch and Secretary and Treasurer of the Kuala Lumpur Cricket Association (KLCA).

Rueben was previously the Legal Adviser to the Malaysian Tenpin Bowling Congress (MTBC) and a former Tender Board Committee Member of the Royal Selangor Club (RSC), Kuala Lumpur.