NFECTIONS of the urinary tract occur alone or in combination with other disease processes in all age groups of both sexes. Consequently, they come to the attention of the physician in general practice as well as the specialist in every field of medicine. The urologist usually sees those patients who have not responded to the usual therapeutic measures. The failure of these patients to respond to treatment is due, largely, to incomplete diagnosis and the consequent inadequate treatment. In turn, the patients' complaints of frequent, difficult, or painful urination may not tell the entire story. All are common complaints, but while they call attention to a disturbed emptying mechanism of the bladder, they do not reflect the abnormality which is usually present in the upper urinary tract. Therefore, unless a thorough investigation is carried out, the concurrent abnormalities in the bladder and elsewhere in the urinary tract are often overlooked; the treatment they require is not instituted; and symptoms recur.