The radiological findings in 13 patients with total aganglionosis coli were reviewed. There was a male to female ratio of 7:6. Fifty-four percent of patients presented in the first week of life, but a significant number (31%) did not present until after 1 month of age. All patients had plain film evidence of bowel obstruction when referred for a barium enema. There were no pathognomonic barium enema findings, and barium enema results covered the entire spectrum of findings which can be encountered in the neonate and young infant with bowel obstruction. Seventy-seven percent had normal calibre colon, 23% had micro colon, 23% had a shortened colon, 46% had colonic wall irregularity, 33% had significant ileal reflux. Delayed evacuation of barium from colon occurred in the two patients who had delayed films. Total colonic aganglionosis should be considered in any infant or young child with plain film evidence of bowel obstruction, whatever the barium enema findings. Hirschsprung's disease and the level of transition can only be definitively diagnosed by biopsy.