A series of 91 staghorn calculi are reviewed. Possible aetiological factors are analysed. A high incidence of hypercalciüria was found, and the significance of this is discussed. The rates of complete stone clearance after conservative surgery are considered for different types of staghorn calculus and it is felt that local circulatory arrest with kidney cooling may be of value in removing stones due to Proteus. The place of elective nephrectomy in the management of staghorn calculi is discussed. Nephrectomy may be the treatment of choice in the management of large, unilateral stones in older patients.