Following a successful and varied career with the Australian Government, William was  appointed by Qantas Airways as its International Security Risk Manager. At Qantas he was responsible for assessing and providing advice on security risks to its Australian and international operations including its aviation businesses, corporate and retail operations. His responsibilities included developing and updating travel security advice for air crew and for Qantas personnel travelling to regions experiencing heightened security environments.

After leaving Qantas, William was contracted as the senior security advisor to several international airlines providing advice to help secure their operations and personnel operating throughout the world, including to and through high-risk regions. Aviation clients included Viva Macao, the US based National Airlines (operating in Afghanistan and other high-risk destinations), Jet Airways, Para Airport in Bhutan, Changi Airport in Singapore, and several Australian and Indonesian airports.

William has undertaken projects for governments and businesses in Australia and internationally. While aviation security was an original focus, he expanded into general security consulting and his work in recent years has included undertaking Security Risk Assessments (SRAs), developing Security Strategies and Concepts of Operations, and conducting security reviews for corporate businesses and government departments.
William has travelled extensively as a security adviser, including regularly to countries experiencing periods of civil or political unrest, or heightened crime levels, including to Argentina, Indonesia, Israel, Papua New Guinea, the Solomon Islands, and the Philippines.

Since joining IR William has managed security risk assessments and security design reports for IR clients in Australia and internationally, including in New Zealand, Papua New Guinea and Malaysia. He is the project lead for the IR team working for Cox Architecture in Saudi Arabia and in 2024 he reviewed security master planning for the CBD of Qiddiya, a major giga-project in Saudi Arabia.

William holds a Master of Business Administration from the University of Sydney, a Bachelor of Arts from the University of Queensland, a Diploma in Security and Risk Management and a Certificate IV in Training and Assessment. He has lectured in Security and Risk Management at Diploma level. William is qualified as both a National Inspector and Security Instructor with the International Civil Aviation Organization (ICAO), and as a Quality Auditor with the International Air Transport Association (IATA).

In 2001 William was presented with a Certificate of Meritorious Service by the Australian Government for his contribution to national security outcomes. For his membership of the ASIS International Global Terrorism, Political Instability, and International Crime Council in Washington, in 2006 William was presented with a Certificate of Appreciation for his Outstanding Contributions and Dedicated Support.