Regular national surveys of all public and private radiation oncology facilities in Australia have been carried out between 1986 and 1999. Workforce data recorded were numbers of radiation oncologists and trainees, radiation therapists, medical physicists and physics technicians, nursing staff, data managers, social workers and clerical staff. Workloads included treatments with megavoltage beams (linear accelerators, cobalt-60), orthovoltage/superficial X-rays, brachytherapy, total body irradiation and stereotactic radiosurgery. Major equipment recorded included numbers of megavoltage and orthovoltage/superficial X-ray machines, planning simulators, computerized dosimetry systems and brachytherapy equipment. The use of radiotherapy beds and the public-private mix of treatments were also documented. Data were assembled for Australia based on each individual state. Within Australia the number of public and private treatment facilities has increased by 44% from 18 in 1986 to 26 in 1999. The population has increased by 16.4%, cancer incidence by 51.8% and megavoltage workloads (fields) by 102%. The number of radiation therapists and physicists and the number of linear accelerators have, in general, increased with the growth in workloads. The number of radiation oncologists has increased by 60% from 4.5 full-time equivalent (FTE) radiation oncologists per million population in 1986 to 7.2 per million in 1999. There is currently a deficit of at least 40 radiation oncologists to be able to treat the 50% of newly diagnosed cancer patients requiring radiotherapy. In addition, a significant deficiency exists in numbers of radiation therapists, nursing staff, data managers, social workers and clerical staff. Clearly the demands for medical physicists has increased but the data are insufficient to comment on deficiencies. Despite the increases in workloads the proportion of patients with cancer receiving radiotherapy remains below 40%. A positive correlation has been shown between the proportion of newly diagnosed cancer patients treated and the number of FTE radiation oncologists, the number of megavoltage machines and number of radiation therapists. This was shown for Australia as a whole, for each state and for the years 1986 to 1999. This was also the case when total megavoltage fields was used as the dependent variable. Multiple regression analysis using the same independent variables confirmed these positive correlations. It is concluded that the low treatment rate with radiation oncology for cancer patients in Australia is due mainly to the lack of resource allocation. The stated commitment of governments and health departments to a 50% treatment rate can only become a reality if there is a concerted effort to increase the numbers of radiation oncologists, radiation therapists, megavoltage machines and support staff. Otherwise at least one in every 10 newly diagnosed cancer patients will continue to be denied adequate and equitable access to radiotherapy - in 1999 that total figure was 9400 persons.