An application of computers to haemodialysis units is presented. In fact these centers are characterised by an enormous amount of data which should benefit from computerization, and therefore in the haemodialysis unit of the Cantonal Hospital, Fribourg, a program has been developed to handle medical data. This program, as far as we know the only one of its kind in Switzerland, has already been in use for the last 9 months. Swiftly, surely and simply it allows storage and retrieval of all the administrative and medical data of each patient. Facility of data retrieval, graphic data display and automatic data evaluation has been found to improve clinical management of patients. It also considerably facilitates scientific work. Once the adaptation period is over it permits definite time savings. We are convinced that, after the necessary period of introduction, computers can be of considerable help in medical care.