He worked in developing countries before starting work as a GP obstetrician and anaesthetist in Thames, later becoming medical superintendent of the hospital there.
Dr McPherson then became chief executive of the Bay of Plenty Health District, leaving to become director of health reforms for the Ministry of Health.
He has also held senior roles with other organisations including Managed Care NZ, Aetna Health, Allianz Asia Pacific, Bruce Mason Centre, Red Cross and the New Zealand Insurance and Savings Ombudsman's Office.
His most recent roles include membership of the Work and Income Board, chairman of Mercy Angiography and Director of Southern Cross Hospitals.
The decision to appoint a chief executive for each of the Wairarapa and Hutt Valley DHBs was made in March to help address the unique health challenges of each region.