Carcinoid tumors are most commonly found in the appendix and small bowel, where they may be multiple. They have a tendency to metastasize, which varies with the size of the tumor. Tumors <1 cm uncommonly metastasize. Tumors >2.0 cm are more often found to be metastatic. Metastasis to the liver and beyond may give rise to the carcinoid syndrome. The tumors cause an intense desmoplastic reaction. Spread into the serosal lymphatics does not imply metastatic disease; local resection is potentially curative. When metastatic lesions are found in the liver, they should be resected when technically feasible to limit the symptoms of the carcinoid syndrome. When extensive hepatic metastases are found, the disease is not curable. Resection of the appendix and cecum may be performed to prevent an early intestinal obstruction by locally encroaching tumor.