Mr Seto worked in the Singapore public sector for nearly 40 years in various professions including military, economic development, diplomacy, public administration and education.

Mr Seto started his career as an Army officer in the Singapore Armed Forces (SAF) for 10 years. For the next 20 years he held various senior positions in the Economic Development Board (EDB), National Science & Technology Board, and Media Development Authority (MDA). At these economic agencies, Mr Seto was involved in industry development, investment promotion and international marketing. Mr Seto joined Republic Polytechnic as its Deputy Principal (Industry Services) in 2009, and was later appointed Senior Adviser in 2018 upon reaching official retirement age. Mr Seto was awarded the Public Administration Medal (Silver) in 2006 and Long Service Medal in 2016.

Mr Seto studied economics in Michigan State University and the University of Michigan. He attended the Advanced Management Programme at the Harvard Business School.