Prostatic calculi are rare in children, infrequent below age 40, and common in males over 50. They may be solitary but usually occur in clusters and are associated with some other disease process (nodular hyperplasia, prostatic carcinoma, metabolic abnormalities). They are most often asymptomatic; however, symptoms that may be attributable to prostatic calculi include reduction of the urinary stream, prostatism, and intense lower back and leg pain. Treatment may be accomplished by transurethral resection, but prostatectomy is the best means to insure complete removal. Prostatic calculi may form by two related mechanisms with obstruction and stasis of prostatic fluid as central entities in both. These mechanisms are calcification of corpora amylacea and simple precipitation of prostatic secretion. They may arise spontaneously, initiating an inflammatory reaction that contributes to their growth, or they may arise as the consequence of another pathologic situation producing acinar obstruction. It appears that infection probably occurs secondary to stone formation.