Omphalomesenteric duct malformations comprise a wide spectrum of anatomic structures and associated symptoms (or no symptoms). They may range from a completely patent omphalomesenteric duct at the umbilicus to a variety of lesser remnants including cysts, fibrous cords connecting the umbilicus to the distal ileum, granulation tissue at the umbilicus, umbilical hernias, and the famous diverticulum of Meckel. Symptoms may involve fecal fistulas at the umbilicus, intussusception/prolapse of ileum at the umbilicus, intestinal obstruction from a variety of causes, melena and anemia, abdominal pain and inflammation, etc. Although symptoms occur most frequently during childhood years (especially in the first 2 years of life), they may occur through adult years as well. Although these malformations are found with equal frequency among the sexes, a significantly greater incidence of symptoms is encountered in males. Although one of the very most frequent malformations to be found (Meckel's diverticulum in 2% to 3% of the population), they are one of the most unlikely to cause symptoms (also Meckel's diverticulum). An awareness of the diversity of these malformations in type and symptomotology is essential to their proper and optimal management.