8 cases of congenital colonic atresias treated between 1968 and 1985 are presented. Questions regarding the aetiology of this rather rare anomaly are discussed. The interference with the mesenteric blood supply often as a result of intrauterine abdominal accidents seems to be a plausible explanation for most cases. We saw a high incidence of associated malformations not stated by other authors. Classification of atresias, diagnostic proceedings and operative management are discussed. The mortality of 50% can probably be lowered by the progress in total parenteral nutrition.