David Mackay began his career at the age of 15 when he was commissioned to illustrate a book on orchids. He has a degree in botany from the University of Sydney and has worked as a scientific illustrator at the Royal Botanic Gardens Sydney, the National Botanic Gardens of Papua New Guinea and (as a visiting artist) at Kew Gardens in London, the University of California at Berkeley and the Linnean Society Herbarium in London. He has illustrated well over 200 books and scientific papers.
More than 5000 of his drawings and paintings have been published. His paintings have been exhibited in Australia, England, USA, Italy, Spain, Japan and Papua New Guinea. His work is represented in public collections in Australia, England, USA and Papua New Guinea and in private collections around the world.