David qualified as a specialist paediatric surgeon in 1992, and since then has worked in Australia, in Britain, and for short periods in other places, largely as a specialist paediatric surgeon, but also in paediatric research. He has a PhD in the physiology and molecular biology of Hirschsprung's disease. He returned from the UK in 2003 to join the paediatric surgery department of Canberra Hospital, and in particular to take part in the new ANU medical school. He has an honorary appointment at the Sydney Children's Hospital, Randwick.
When asked about how his faith and medical work relate, David says:
My 33 year engagement with the UMN hospital at Tansen in Nepal (originally with Interserve, which we still support), and the other overseas trips (Gaza for 14 years, Honiara for 5 years, and single trips to Mongolia and Zambia) are all informed by a spirit of Christian service. I tell audiences that I do them because they are fun and interesting, and that is true, but not the whole story. That experience has allowed me to speak on various platforms on the various aspects of third world work (which I hope does not degenerate into medical tourism). I have supported the Christian medical students here at ANU, and in the past have been a member of the Christian Medical and Dental Fellowship.