Dr. Oh Ei Sun is the Principal Adviser for Pacific Research Center, Malaysia, and Adjunct Senior Fellow at the S. Rajaratnam School of International Studies, Nanyang Technological University, Singapore, where he researches on the political economy of Asia Pacific, and Southeast Asia's interactions with China.

He was also senior research fellow and lecturer in various public and private universities in Malaysia, China, Australia and the United States. He is a council member of the Commonwealth Magistrates and Judges Association and of China's Overseas Exchange Association, and president of the Sabah Ma Zhong (Malaysia-China) Friendship Association.

He has also been an avid commentator and columnist on politics, economics and current affairs for various international media. He served as administrative officer at the International Telecommunication Union, and scientific and legal consultant to the United Nations Office for the Coordination of Humanitarian Affairs in Geneva, Switzerland.

He earned his JD (law and policy), MBA, MSc (Engineering), BSc (Mechanical Engineering), BSc (Aeronautical Science and Engineering), BA (German), all from the University of California, USA.