DISEASE of the urinary tract is a common cause of illness during early life, and is responsible for a significant number of deaths in this age group (3). Many of these patients may be benefited by surgery, particularly if urinary obstruction is present. Campbell (4) states that “various combinations of obstruction and infection constitute over 90 per cent of the major urologic problems in children.” It is obvious that early diagnosis is essential if surgical intervention is to be effective and that roentgen visualization of any anatomic abnormality is an important guide in the surgical approach. Of the two available roentgen methods, retrograde and descending urography, the latter has the following advantages: (1) It is a more physiologic method and is well adapted for visualization of mechanical obstructions provided the kidneys are capable of secreting the dye. (2) It is a safer and less complicated procedure than retrograde pyelography, which usually requires the use of a general anesthetic and often results in considerable trauma, even if a small cystoscope is used (9, 11). Retrograde pyelography may be employed if indicated and physically possible. The conservative method of approach, however, is excretory urography, which with few exceptions should precede the use of instrumentation. Indications for Excretory Urography Pyuria, pain, and hematuria are the classical signs of urinary tract infection. They are frequently accompanied by fever, dysuria, frequency, enuresis, vomiting, diarrhea, or other systemic manifestations. Urinary tract infection is an indication for excretory urography with one possible exception, namely, a single acute attack of pyuria in a female child, with prompt response to therapy. Such infection in a male child should be thoroughly investigated because, although less common than in the female, it is more often associated with congenital malformations. Infection may not be detected unless urine examinations for pus cells and bacilli are done whenever unexplained fever is present. Chronic or recurrent infection always justifies urography regardless of sex. Symptoms of urinary tract obstruction may be misleading if unassociated with infection. Obscure abdominal pain due to obstruction produced by congenital malformation may be the only finding. Such pain is often referred to the umbilicus or elsewhere in the abdomen. Persistent or recurrent vomiting may be the only indication of urinary tract obstruction. Any of these symptoms indicates the employment of urography when it cannot be explained on the basis of disease outside of the urinary tract. Other indications for excretory urographyare abdominal tumors, orthostatic albuminuria, and visible congenital malformations of the external genitalia. Problems and Methods Excretory urography during early life presents problems which are seldom met with in adults. Satisfactory urograms cannot be obtained unless these difficulties are overcome.