OBJECTIVES. The aim was to analyse the consumption of different items in conventional treatment of acute myeloid leukaemia (AML) and their cost, in order to evaluate the economic consequences of new treatment strategies. DESIGN. Data on items of treatment were gathered retrospectively from case notes, including amount and date. Prices were gathered from price lists made up for internal billing/accounting. SETTING. The patients were all treated in a hospital with excellent treatment and service facilities. SUBJECTS. Seventy-three AML patients treated from 1973 to 1980, all since deceased, were compared with 54 patients treated from 1981 to 1988, of whom 14 were alive at the end of the observation period. INTERVENTIONS. The patients were treated according to randomized treatment protocols to achieve complete remission. Maintenance treatment or consolidation courses were given. In relapse, new induction treatment was given. MAIN OUTCOME MEASURES. Complete remission and survival were registered. The costs were divided into basic hospital costs and patient-specific costs. RESULTS. The mean total treatment cost for an AML patient in the 1970s was 211,138 SEK, and in 1980s 356,911 SEK. (UK 1 pound = 10.57 SEK, US$1 = 5.91 SEK 1990). All treatment costs increased between the periods: hospital costs by 20%, and patient-specific costs by 186%. Antibiotics, cytostatics and outpatient department costs had increased the most. The mean survival time almost doubled, and in the 1980s group there were several long-term survivors. CONCLUSIONS. The costs for AML treatment increased considerably from the 1970s to the 1980s. The effectiveness of these treatments increased as well, resulting in increased rate and duration of survival, and several patients were long-term survivors. It was not possible to identify the cost consequences of separate new technologies.