Intussusception is an important cause of intestinal obstruction and bowel necrosis in infants under 2 years. Most frequently the ileocaecal junction is involved. Various aetiologic factors, such as Meckel's diverticulum and lymphoid hyperplasia have been identified. Hydrostatic reduction of the intussusception should be attempted, but delay in diagnosis frequently leads to surgical intervention, because of failing reduction. We report a case of a 4-month-old boy whose ileocaecal junction was intussuscepted into the rectum, and therefore could be palpated by rectal examination. Unsuccessful hydrostatic reduction and bowel necrosis because of delay in diagnosis, made surgical intervention necessary. A terminal ileostomy was performed. A second case report considers a 10-month-old boy whose ileocaecal junction was intussuscepted into the colon sigmoideum. Because there was no delay in diagnosis, this intussusception could be reduced hydrostatically. The procedure however was difficult because of a dolichosigmoideum. Recent literature is also reviewed.