Pneumatosis cystoides intestinalis (PCI) is a disease in which small gas-filled cysts appear in the intestinal wall. Four cases presented here demonstrate the diversity of the associated diseases. In two of the patients constipation prob-ably played a role; in the third patient decreased colonic motility, elevated intestinal pressure and increased mucosal permeability in the context of enteritis treated with codeine was the underlying problem; in the fourth high protein feed-ing and bowel ischaemia was diagnosed. Various aetiologies are presented in the literature. There is no specific history and physical or laboratory findings do not help to diagnose PCI. Plain abdominal film, ultrasound, computer tomogra-phy, magnetic resonance imaging, barium contrast studies and/or endoscopy may be necessary for diagnosis. Therapy is based on enhancing partial oxygen pressure in the bowel wall. PCI usually runs a benign course.