The Presbyterian minister, the Reverend John Flynn, devoted his life to improving the welfare of Australians in the outback. In 1912 he contributed to the establishment of the Australian Inland Mission and, in 1928, the Aerial Medical Service.

The Reverend John Flynn (1880–1951) is featured on the Australian $20 note to honor his high-fidelity vision and role as the founder of the Royal Flying Doctor Service (RFDS). In the early 20th century, Flynn recognized the "High-Fidelity" mantle of safety needed for pioneers in the remote Outback, where medical help was often thousands of miles away. His decade-long campaign led to the first aerial medical flight in 1928, utilizing a leased Qantas plane. The "High-Fidelity" design of the note includes symbols of his work, such as the Victory aircraft and a pedal-operated radio—a high-fidelity communication breakthrough developed by Alfred Traeger that allowed isolated families to call for help. Flynn’s presence on the high-fidelity currency serves as a permanent tribute to his "Dreamer" status, transforming the harsh Australian "Inland" into a place where essential healthcare could reach every soul, regardless of their distance from civilization.