A fellow member of the Institute of Singapore Chartered Accountants, Chay started his career as an Audit/Tax Assistant at Arthur Young & Co in 1980 after graduating with a degree in Accounting from Nanyang University. He was co-founder and Group CFO of listed Natsteel Electronics Ltd from 1992, and Founding Director of listed ECS Holding Ltd in 1998. After a merger, he was named Asia Pacific Head of Finance of US-based MNC Selectron Technology Co ( Now known as Flextronics Group) in 2000. Chay retired and found his own firm Autoscan Technology Group and became its Chairman since 2003. Mr Chay has also served at the board and committees of NKF ( 2010-2018), Finance committee of SingHealth Fund ( since 2018), SMU Business School Advisory Board ( 2010-2016), and Dingyi Music Company since 2019. Currently, Mr Chay served as a Board member and Chairman of the Audit Committee of SGX listed Trek2000 Technology Ltd.