Background: Capsule endoscopy has demonstrated its clinical utility in the evaluation of the small bowel and, accordingly, it has been suggested that it could be useful for the identification of small intestinal polyps in patients with polyposis syndromes. Objectives: To establish the effectiveness of wireless capsule endoscopy for detecting small bowel polyps in patients with hereditary gastrointestinal polyposis syndromes in comparison with barium contrast series. Patients and Methods: Consecutive patients with gastrointestinal polyposis syndromes were included. Small bowel follow-through series and capsule endoscopy were performed within one-week in a blind fashion. Number and location of polyps were analyzed. Results: Twenty-four patients with familial adenomatous polyposis (n = 20) or Peutz-Jeghers syndrome (n = 4) were included. Capsule endoscopy detected small bowel polyps in 7 out of 24 patients (29%), whereas barium contrast study identified small intestinal polyps in only 3 of these 7 patients. In the four remaining patients, all of them with familial adenomatous polyposis, polyps detected by the capsule but missed in radiographic series were located at either ileum (2 cases), jejunum (1 case) or duodenum (1 case). No procedure-related complication was observed in any patient. Conclusions: Wireless capsule endoscopy is a high accurate technique for the detection of small bowel polyps, and it represents a valuable alternative to barium contrast series in the surveillance of patients with hereditary gastrointestinal polyposis syndromes. Background: Capsule endoscopy has demonstrated its clinical utility in the evaluation of the small bowel and, accordingly, it has been suggested that it could be useful for the identification of small intestinal polyps in patients with polyposis syndromes. Objectives: To establish the effectiveness of wireless capsule endoscopy for detecting small bowel polyps in patients with hereditary gastrointestinal polyposis syndromes in comparison with barium contrast series. Patients and Methods: Consecutive patients with gastrointestinal polyposis syndromes were included. Small bowel follow-through series and capsule endoscopy were performed within one-week in a blind fashion. Number and location of polyps were analyzed. Results: Twenty-four patients with familial adenomatous polyposis (n = 20) or Peutz-Jeghers syndrome (n = 4) were included. Capsule endoscopy detected small bowel polyps in 7 out of 24 patients (29%), whereas barium contrast study identified small intestinal polyps in only 3 of these 7 patients. In the four remaining patients, all of them with familial adenomatous polyposis, polyps detected by the capsule but missed in radiographic series were located at either ileum (2 cases), jejunum (1 case) or duodenum (1 case). No procedure-related complication was observed in any patient. Conclusions: Wireless capsule endoscopy is a high accurate technique for the detection of small bowel polyps, and it represents a valuable alternative to barium contrast series in the surveillance of patients with hereditary gastrointestinal polyposis syndromes.