Gregory is from the Waanyi and Jaru Aboriginal people and grew up in Cloncurry and Mount Isa. He is a medical anthropologist with a masters degree in medical science.
Gregory has worked in Aboriginal and Torres Strait Islander education, youth work, native title, alcohol and drugs, sexual health, healing and addictions recovery. He wrote an accredited Indigenous health curriculum for all medical schools in Australia and New Zealand, founded the Leaders in Indigenous Medical Education (LIME) Network, co-wrote a national Aboriginal and Torres Strait Islander health workforce strategy, established the Aboriginal and Torres Strait Islander Healing Foundation Ltd in the wake of the federal apology to Indigenous Australians, and has advised federal ministers on Indigenous health inequality.
Gregory is Executive Director of ABSTARR Consulting, and an adjunct senior lecturer in Aboriginal health in the Faculty of Medicine, Nursing and Health Sciences at Monash University. He joined the Bangarra board in November 2011.