Dr. Ong has an illustrious career spanning over 45 years in the surveying profession, covering both public and private sectors. He was the former Senior Partner of Davis Langdon & Seah and is currently the Executive Chairman of Benchrisda Associates Sdn Bhd, a quantity surveying and project management consultancy firm.

Dr. Ong was the President of the Royal Institution of Surveyors Malaysia (RISM) from 2002 to 2004 and has been instrumental in shaping the surveying profession in Malaysia through various leadership roles and contributions to professional standards and education.

He was the 130th Global President of the Royal Institution of Chartered Surveyors, RICS (2011-2012), making history as the first non-British, the first Asian, and the first Malaysian to be elected to this prestigious position. During his tenure, he championed the globalization of surveying standards and the expansion of RICS's influence across Asia.

He also took on the chairmanship of the Standard Setting Committee for the development of the International Construction Measurement Standard (ICMS), a landmark initiative to create a global standard for benchmarking and comparing construction costs across international markets.

He was the Chairman of FIG Commission 10 (Construction Economics and Management) from 2007 to 2010, where he led international collaboration efforts to advance construction economics research and practice among member countries of the International Federation of Surveyors.

Dr. Ong is a multiple awards winner, receiving numerous recognitions for his outstanding contributions to the surveying profession. His accolades include the RICS President's Medal, the RISM Gold Medal, and the Malaysian national honour of Kesatria Mangku Negara (KMN), conferred by the Yang di-Pertuan Agong in recognition of his distinguished service to the nation.