&NA;The mechanisms linking the psyche and cerebral control of colonic motility are reviewed, including the psychologic profile of patients with functional bowel disease, and human and animal experiments that clarify this connection. Other abnormalities in functional disorders such as hormone abnormalities and myenteric plexus changes are also covered. The results of surgery for constipation are now clearly established. Calcium is an important regulator of smooth muscle activity; its role and therapeutic application are discussed. An update on measurement of colonic transit and motility is included. Nonsteroidal drugs and complicated diverticular disease are an important association. Circulating hormones and colonic and pouch motility are reviewed. Greater characterization of colonic hormone and neurotransmitter receptors is discussed. Lastly, a clinical curiosity, ciguatera fish toxin causing diarrhea, is discussed.Current Opinion in Gastroenterology 1992,8:12‐18