A series of 31 children with myelomeningocele who have undergone urinary diversion by cutaneous uretero-ileostomy is presented. The complications reported in 11 other series are analyzed. The most serious complications in children are peritonitis secondary to urine leakage at the ureteroileal anastomosis, and renal deterioration due to silent obstruction at the same site. The most common late complication in children is stricture of the abdominal stoma, which is shown to be growth-related. A description is given of the urologic problems encountered in children with myelomeningocele before and after diversion, with emphasis on the progressive effects of hydronephrosis and chronic urinary tract infection. The renal damage caused by these two conditions can be prevented or ameliorated by diversion via the cutaneous uretero-ileostomy.