David Stewart is the Chief Executive Officer and Managing Director of Leighton Holdings Limited, the parent company of one of the world's major project development and contracting organisations and the world's largest contract miner. In 2009/10, Leighton earned revenue of $18.6bn and a profit after tax of A$615m.

Listed on the Australian Stock Exchange since 1962, Leighton Holdings is a top 30 company by market capitalisation and has its head office in Sydney, Australia. Leighton Holdings owns seven diverse and independent operating companies: Leighton Contractors, Thiess, John Holland, Leighton International, Leighton Asia, Al Habtoor Leighton Group and Leighton Properties. These operating companies provide development, construction, contract mining, and operation and maintenance services to the infrastructure, resources and property markets. They operate in Australia, New Zealand and more than 20 countries across Asia and the Middle East from headquarters in Australia, Hong Kong, Kuala Lumpur and Dubai. These operating companies directly employ around 47,300 employees.

David is a civil engineer with 35 years experience, managing operations throughout Australia and South-East Asia in the construction and mining industry. He joined the Leighton Group in 1985 and held various roles with Leighton Major Projects and Thiess before joining John Holland in 2000 where he headed that company's construction business. In early 2006, David was appointed John Holland's Managing Director and in 2009, to the position of Chief Operating Officer at Leighton Holdings, responsible for John Holland, Al Habtoor Leighton Group and Leighton Properties. David was appointed Chief Executive Officer of Leighton Holdings Limited on 1 January 2011.