Atresia or stenosis of the colon is a rare congenital anomaly. In 1673, Binninger reported the first case of colonic atresia, and Gaub reported the first survival with this anomaly in 1922. In recent years the number of survivals has increased. A better understanding of etiology as well as the marked increase in successfully treated patients reported on in the world literature has prompted this present review. Definitions and Classification Definitions. —In this review we shall consider only congenital atresia and stenosis of the colon and shall not include malformations of the anus and rectum (particularly Type 4 imperforate anus,16 which might be considered a form of atresia of the pelvic colon, but will not be discussed since it is traditionally classified as a form of imperforate anus). The term "atresia" refers to complete occlusion of the lumen of the bowel, while stenosis refers to partial occlusion. Although occasional