The use of ultrasound in the diagnostic and therapeutic management of 5 patients with renal abscesses is described. A spectrum of ultrasonic findings was noted, with the majority of the lesions being anechoic (3 cases). However, a few lesions showed a mixed pattern (2 cases). Ultrasonic aspiration of abscess fluid for culture and sensitivity obviated an operation in 1 case. For the first time, ultrasonically guided, percutaneous, indwelling catheter drainage of a renal carbuncle is reported. Since the patient had failed to respond to systemic antibiotic therapy this technique saved the patient from undergoing an operation. The clinical and ultrasonic findings in the 6 previous case reports of abscesses are reviewed.