[1] He was awarded a Ph.D. from Adelaide University in 1982 for work on Prostanthera.
He then became herbarium curator and a lecturer at the Papua New Guinea Forestry College, Bulolo (1976–1979).
In Australia, he has been senior botanist at the National Herbarium of Victoria (1982–1987), and botanist (and principal research scientist) at the National Herbarium of New South Wales (1987–2015).
In 1994-1995, he was Australian Botanical Liaison Officer at Kew.
While with the National Herbarium of New South Wales, he managed the Australia’s Virtual Herbarium Project for New South Wales, and was scientific editor of the journal Telopea from 2013 to 2015.