Two thousand eight hundred thirty-seven cases of carcinoid tumor from files at the National Cancer Institute were analyzed statistically. Tumors were found in the lung, ovary, and biliary and gastrointestinal tracts. Most were in the appendix, rectum, and ileum. Age-adjusted incidence rates were higher for black males, except for lung carcinoids. Carcinoids showed several differences from other kinds of tumor, including a low age for appendiceal and lung cases and low male/female and black/white ratios in the lung. Percentages of concurrent neoplasms and multiple carcinoids were low compared to other series. Five-year relative survival rates ranged from 99% (appendix) to 33% (sigmoid colon). Survival for colon cases was not so low as expected on the basis of the high rate of metastasis. Some appendiceal carcinoids were metastatic and may have killed 1 patient. Findings are compared with other studies.