One hundred fifty-four patients with gastrointestinal carcinoid tumors were surgically treated at our institution between 1972 and 1982. The most frequent primary sites were the ileum (43%), rectum (30%), appendix (11%), jejunum (6%), stomach (6%), and duodenum (1%). Asymptomatic tumors were discovered incidentally in 93 patients (60%). Symptomatic tumors were common (48%) among the group with ileal carcinoid tumors. Except for endoscopy, preoperative studies were of limited value. The malignant carcinoid syndrome was present in 12 patients (nine with ileal tumors). One hundred forty-seven patients underwent surgical or endoscopic resection of the primary tumor; the overall operative mortality rate was 2.6%. Of significance was the high incidence (18%) of metastasis from ileal primary tumors smaller than 1 cm.