Engineer (Er) Chong Kee Sen is the immediate past President of the Institute of Engineers Singapore (IES). He has served on the IES Council for more than 10 years, including being its Honorary Secretary for four years. Er. Chong joined IES as a member in 1992 and is now a Fellow of the Institution.

Er Chong was a key mastermind behind the industry-led accreditation initiative for Resident Engineers (RE) and Resident Technical Officers (RTO) and was the founding chairman of the Joint Accreditation Committee formed by IES, the Association of Consulting Engineers Singapore (ACES) and the Building Construction Authority (BCA) for the registration of Civil and Structural REs and RTOs. He also co-chaired the development of SS 593: Code of Practice on Pollution Control in partnership with the National Environment Agency (NEA). Er Chong also sat on various industry and government agencies committees as an IES representative.

Er Chong graduated from the Nanyang Technological University (NTU) in 1987 with an Honours in Civil and Structural Engineering. Presently the President of the NTU Civil and Environmental Engineering Alumni Association (NCEEAA), Er Chong has organised fundraising golf tournaments to fund bursaries and book prizes for deserving Civil and Environmental Engineering students. He also assisted the NTU Admissions Office with student admission interviews and co-chaired NTU class reunion functions. He is presently a member of the NTU program advisory committee for the B. Eng (Civil) program. In recognition of his outstanding contributions towards fostering closer ties between the Alumni and the university, Er Chong was presented with the NTU Nanyang Alumni Service award in 2008.

Er Chong is a board member of the Professional Engineers Board, where he chairs interview panels for the registration of professional engineers. Er Chong has been a registered Professional Engineer since 1996 and is also an ASEAN Chartered Professional Engineer.

As Director of Engineers 9000 Pte Ltd, a civil and structural consulting engineering company, Er Chong has executed various large infra-structural projects as a professional engineer. These projects include petrol-chemical plants, pharmaceutical plants, combined cycle power plants, land reclamation and soil improvement projects, near shore marine structures and many other industrial and building projects.