Dr Joan Croll AO (1928–2022), radiologist and physician, studied medicine at the University of Sydney and commenced practising in 1975. A pioneer in the field of breast cancer treatment, she promoted the introduction of mammography and helped establish the National Breast Cancer Screening Program. Also a conservationist, Croll was one of a group of thirteen women – the Battlers for Kelly's Bush – whose campaign to protect bushland in Sydney's Hunters Hill in the early 1970s led to the world's first green ban.