Clark has worked in accounting standard-setting roles in Australia, the USA and the UK since 1987. His current principal responsibilities at the AASB concern Accounting Standards-related projects (particularly public sector projects), climate-related financial disclosures, and publication and regulatory matters. Clark has been involved with many areas over the years, including implementation issues through the former Urgent Issues Group and a total of 8.5 years as Technical Advisor to the Australian member of the International Public Sector Accounting Standards Board.
Prior to becoming a standard setter, Clark worked for a predecessor firm of Ernst & Young, in auditing, technical and education roles, based in Melbourne, but also with experience in Singapore and Indonesia.