Mahadi grew up in Penang, Malaysia, attended the Hutchings Primary School and the Methodist Boys’ Secondary School and then had his tertiary education in the United States of America, graduating  from Brandeis University, Massachusetts with a Bachelor of Arts (Economics) degree in 1976 under the Wien International Scholarship Program. After graduation, he worked for a commercial bank and a Nomura-affiliated investment bank and completed his Diploma in Banking from the Institute of Bankers, London. He graduated from the University of London with a LL.B. (Hons), completed his Certificate in Legal Practice, Malaysia and has been admitted as an Advocate and Solicitor of the High Court of Malaya.

He was in the service of PETRONAS, the national petroleum company of Malaysia for 33 years and held positions in the international marketing, corporate planning, finance, oil downstream planning and legal services divisions of PETRONAS. Mahadi was the Company Secretary/Legal Advisor of PETRONAS Gas Berhad, a Malaysian public-listed company. For the Dragon LNG Regasification Joint Venture Project in Milford Haven, Wales, UK he was the PETRONAS Legal Advisor and concurrently the PETRONAS nominee Director of Dragon LNG Ltd. He has also experience in international energy, oil, gas and petrochemical projects in Canada, Australia, Uzbekistan, Sudan, India, China,  Philippines, Vietnam, Indonesia and other South-East Asian countries and advised on upstream oil and gas production sharing contracts and M&As, JOAs, drilling contracts, FPSO/FSO agreements, FLNG projects and abandonment & decommissioning in Malaysia and South-east Asia.

Recognising that the energy supply and demand system is transforming very rapidly in the context of climate change and the transition to new energy, he has a keen personal interest in energy management and transformation in Malaysia and has acquired knowledge and expertise in the new energy sectors –  regulatory framework, carbon credit, waste-to-energy, solar power, hydrogen and river hydropower, including the related power purchase agreements.

Membership:
• Association of International Energy Negotiators [AIEN] (previously known as AIPN)
• Society of Construction Lawyers, Malaysia
• Malaysian Petroleum Club, Kuala Lumpur
• Alliance Francaise, Kuala Lumpur
• Putrajaya Lake Club

Interests: Reading, flora and gardening.