The many manifestations of carcinoids will continue to puzzle and intrigue surgeons. Because these are dynamic tumors which produce multiple hormones with many potential side effects, an aggressive surgical debulking of them is advocated. Even in the presence of metastatic disease, some long-term survival can be anticipated. The most debillitating aspect of this tumor to the patient is the carcinoid syndrome. The symptoms occur erratically and are often not well controlled by presently available medication. Although metastatic disease present at diagnosis is most commonly seen with jejunoileal carcinoids, colorectal carcinoids appear to be the most lethal tumors. However, they are rarely associated with the symptoms of carcinoid syndrome. Carcinoids may often be associated with other types of tumors, some of which are known to produce their own hormones. Survival of the patients seems to be related to their other tumor type rather than the primary carcinoid. The clinician should be aware of the strong association of carcinoids with peptic ulcer disease. The ulcer diathesis is probably related to ectopic histamine production and can usually be controlled by cimetidine and antacids, although surgical intervention may be required.