Two-hundred-and-forty-eight full-blood tribal Aborigines from the West Kimberley region of Western Australia were surveyed for the prevalence of coronary heart disease, and compared with the known prevalence in whites in the country town of Busselton, WA. The prevalence was found to be greater among the Aborigines, with 7% of men, and 11% of women being found to have "probable" coronary heart disease. Seven per cent of the population had electrocardiographic changes characteristic of frank ischaemia. The major risk factors contributing to this high prevalence were hypertension, diabetes mellitus, and obesity. Thirty-seven per cent of the Aborigines were hypertensive, and 17% had diabetes mellitus.