Herein we present the experience of our hospital, which spans a period of 10 years, in the diagnosis and treatment of retroperitoneal abscess. The clinical features, origin and localization of the abscesses are described. We underscore the diagnostic value of ultrasound (US) and computerized tomography (CT) which afford a sensitivity of 86.3% and 100%, respectively. An increased incidence of abscess from gram-positive bacteria was observed in i.v. drug addicts.