The annual cost for a concentrated, high volume radiation therapy (RT) department during 1977 was 3.79 million Canadian dollars (C$). From a population of 1.14 million, 955 patients were treated with RT during 1977 at an average cost of C$3969 per patient. It is estimated that 225 will survive 15 years at a cost of C$1123 per survivor-year. The area under the RT survival curve presented indicates that RT given in 1977 will contribute to 5730 person-years of life at a cost of C$661 per person-year or C$1.82 per person-day (little more than the cost of a city bus ride). The cost to the community is C$3.32 per head per year. A 6 MV workhorse linear accelerator and its vault will contribute to one person-year of life at a cost of C$35.04 (or C$0.68 per person-week). RT is cheaper than various listed medical and surgical procedures in terms of cost per procedure or cost per year of life gained. All costs are adjusted to the 1988 C$.