Thomas is a chartered accountant with extensive public practising experience. He has undertaken financial reporting advisory and assurance services for a wide range of particular clients including associations, charity bodies, SMEs, and regulated entities (such as those under EMB, SWD, LawSoc and SFC).

For more than a decade, Thomas has involved or facilitated in financial and information systems assurance, operational risk management reviews, and advisory assignments where the subject matters included both information systems (such as billings, assessment of operational and security risks) and financial systems (such as financial reporting, financial due diligence, financial information controls). He has served clients in the fixed-line and mobiles tele-communications, brokerages and credit card operations industries, for companies listed and unlisted, both local and overseas.

He was notable to be one of the first CPA (Practising) in Hong Kong who cross-holds the CISSP and CISA designations. He was also one of the earlier full members in the PISA Society, and has memberships in other bodies including ITAA, ISACA, TIHK and SCAACPA. He obtained professional certificates in both international financial reporting and assurance. He has been a registered module facilitator and an authorized supervisor for the HKICPA QP articling students. Thomas has his own public practice (Thomas H S Tsang Certified Public Accountant).

Thomas is now serving as the Hon. Secretary and Treasurer of Professional Information Security Association. Please feel free to reach him at SecTre@pisa.org.hk .