Prof Lui retired in 2008 after serving 41 years MINDEF and as Chief Defence Scientist in the last 22 years. His last appointment in the SAF was acting Director Joint Operations and Plans Directorate. He completed 20 years of service in the SAF in the rank of Colonel and continued service as a Non-Uniformed SAF (NUSAF) officer.

He is currently Temasek Defence Professor and member of Development Projects Advisory Panel, of Ministry of Finance. He serves on the steering committee of Changi Airport and Tuas Mega Port and various steering committees and expert panels. He is chairman of MPA’s MINT Fund Steering Committee. He is chairman of the board of directors of Sembcorp Specialised Construction Pte. Ltd. He is chairman of the management board of Singapore Nuclear Research and Safety Institute.

He was awarded the first MINDEF postgraduate fellowship in 1971 and graduated in 1973 with a master’s degree in operations research and systems Analysis from the US Naval Postgraduate School, Monterey, California. He was appointed Special Projects Director to plan and implement large scale projects for the SAF.

Prof Lui shares his knowledge and experience in the concept development of military systems and the implementation of large-scale system projects in various committees and through lectures at the Defence Management Systems Course (DMSC) and other organizations.

He was conferred honorary Doctor of Science by SUTD in 2025

He received the National Day Award 2025 Distinguished Services Order.