 Reilly joined the Royal Australasian Ornithologists Union (RAOU) in 1956, which she served as Publicity Officer 1966–1967, on the Field Investigations Committee 1969–1972, as President 1972–1975, and as the Chair of the Atlas Committee 1976–1982.From 1969 to 1970 she was President of the Bird Banders' Association of Australia.From 1964 to 1981 she was the Honorary Regional Victorian Organiser of the Australian Bird and Bat Banding Scheme.