In this article the costs of prevention and treatment of decubitus (bed sores) are calculated and an analysis is made of the structure of these costs. Using documented figures on the prevalence of decubitus in hospitals and nursing homes and of prices related to decubitus prevention and treatment as made in a hospital (University Hospital Utrecht, the Netherlands) in which decubitus is treated according to a strict protocol, total costs were calculated by extrapolation. Prevention of decubitus costs Dfl. 95,-per day per patient, treatment of decubitus stages I and II Dfl. 133,-and of stages III and IV up to Dfl. 175,-. These figures result in annual costs of Dfl. 223 million for prevention, Dfl. 125 million for treatment of stages I and II and of Dfl. 122 million for stages III and IV. Together with a mean occupation of hospital beds of 74% this amounts to a total of Dfl. 350 million per year for hospitals and a similar amount for nursing homes, or Dfl. 700 million in all. The costs of decubitus in home care are not known, but believed to be of the same order of magnitude. These figures apply to a total population of the Netherlands of 15 million. Extension of the hospital stay of the patients accounts for 65% of the costs, increase in attendance of nursing staff for 25% and all other actions (physical therapy, dietary adjustments, medication) for only 3%. Special beds cost about 7% of the total amount. The costs of prevention and treatment of decubitus are high (in hospitals and nursing homes alone approximately Dfl. 700 million per year) and tend to increase since the population is growing older and decubitus is occurring mainly in the older population. Only 7% of these costs are spent on the use of special beds. Since the costs of the leasing of these beds are usually not included in the hospital budgets, the financing of these important tools in prevention and treatment of decubitus is increasingly difficult.