Endoscopic biopsy is an accepted technique for obtaining samples of small bowel mucosa for histological examination. In this study a comparison between endoscopic forceps biopsies and capsule biopsies in estimating disaccharidase enzyme activity in the small bowel was evaluated. Disaccharidase levels on 168 consecutive small bowel biopsies obtained by either endoscopic biopsy or capsule biopsy were reviewed retrospectively. There was no significant difference in enzyme activity in samples collected by either method. Another 18 patients had simultaneous endoscopic and capsule biopsies from the second part of the duodenum. Again, there was no difference in enzyme activity between samples collected by either technique at the same level in the duodenum. The disaccharidase activity in forceps biopsies taken from the second part of the duodenum is equivalent to those obtained by capsule biopsy.