Review of 8 patients with retroperitoneal fibrosis treated in our unit, 7 between 1985 and 1990 and one secondary to chronic use of non-steroidal anti-inflammatory agents diagnosed in 1980. In five patients no underlying reason was found and the remaining three were considered to be secondary (two to drugs and one to pelvic radiotherapy). Diagnostic and therapeutic approaches as well as patient's evolution are analyzed, also reviewing the existing literature.