Prior to 1948, when the first distal colonic resection with preservation of continence was performed for Hirschsprung's disease, there was no clear understanding of the etiology of the disease. Early explanations for the cause of the disease included mechanical obstruction, "neurologic imbalance," and congenital malformation of the entire colon. No medical or surgical treatment had proved successful in treating the disease. It is generally assumed today that the absence of ganglion cells was widely known and accepted as the cause of Hirschsprung's disease prior to 1948 and that this led to the concept of distal colon dysfunction and formed the basis for the distal colonic resection. As a matter of fact, it played no role whatsoever in devising the successful operation. The rare absence of ganglion cells was widely held to be produced by the massive distention and chronic stasis in the megacolon and was considered of no pathologic significance. This report reviews the early work in developing the concept of a distal physiologic obstruction that led to a successful surgical treatment.