He was appointed as the inaugural Head of the Addiction Medicine Service at the Royal Melbourne Hospital and is Medical Director of the Substance Withdrawal Unit at the Melbourne Clinic Richmond. Professor Gijsbers is the national President of ISCAST, a group of Christians interested in the interaction between science and religion and the past National President of HealthServe Australia, an organisation of Christian health professionals who seek to provide health and development overseas. He is a member of the Board of the International Christian Medical and Dental Association.