A retrospective survey has been done on 175 chronic patients who underwent dialysis in one center, between January 1982 and June 1992. The purpose of the work was to evaluate the use of the first treatment and the cause which determined a change of treatment. Diffusive haemodialysis and CAPD were the most frequent first choice techniques, respectively in extracorporeal and peritoneal dialysis, whereas changes were conditioned by the need for a more personalized treatment, especially in the filed of extracorporeal dialysis.