He is currently the Director of Cluster Services of the Hong Kong Hospital Authority. He previously was Hospital Chief Executive of Tuen Mun Hospital and the Cluster Chief Executive of New Territories West Cluster of the Hospital Authority. Dr Ko moved from clinical medicine to health services management in 2008 and served as the Chief Manager (Strategy, Service Planning and Knowledge Management) and later the Chief Manager (Patient Safety & Risk Management) of the Hospital Authority Head Office until the appointment to Hospital Chief Executive of Pok Oi Hospital and Cluster Chief Executive of New Territories West Cluster in 2012 and 2014 respectively; and the appointment to his current position in 2018.