Despite scepticism in the English speaking literature today there is international agreement on the existence of neuronal intestinal dysplasia and other intestinal malformations which may well be differentiated from classical aganglionosis. In large series of patients with neuronal intestinal malformations it was found that only one fourth suffers from Hirschsprung's disease. Therefore this article presents the state of our recent knowledge of classical aganglionosis and allied disorders which include hypoganglionosis, neuronal intestinal dysplasia type A and B, immaturity of ganglion cells and not classifiable dysganglionosis. We want to emphasize the morphological differentiation of these neuronal intestinal malformations. However, the relationship between morphological findings, clinical symptoms and bowel motility remain to be clarified by further studies.