Provisional reports from the Intercollegiate British Society of Gastroenterology National Colonoscopy audit show completion rates of 57-77% for the procedure and poor levels of training and supervision. We prospectively audited all aspects of colonoscopy performed at a combined district general hospital and specialist endoscopy unit. Details of referral, examination, endoscopist, complications and follow-up were recorded and patients were sent questionnaires for long-term follow-up. 505 patients (246 male) underwent colonoscopy by 27 different endoscopists. Their median age was 57 years (range 13-92) and 93% were outpatients. 64% patients were symptomatic and 36% were having surveillance or follow-up colonoscopy. The overall caecal intubation rate was 93%, with little difference between surgeons, physicians and experienced trainees (89%, 92%, 94%) and specialist endoscopists (98%). In only one case was an inexperienced trainee (<100 procedures) unsupervised. Pain scores estimated by the endoscopist were well matched with those given by the patient-medians 29 and 26 (maximum 100) respectively. Median satisfaction score was 96 (maximum 100). Polyp pick-up rate was 26.9% and there were 11 new cancers. 16 (3%) minor immediate complications were recorded-5 oversedation, 6 vasovagal attacks, 3 polypectomy haemorrhages and 2 mucosal injuries (neither requiring treatment). 3 patients died within 6 months of follow-up but no death was colonoscopy related. Completion rates in this setting were adequate for all endoscopists studied. Patient satisfaction with the procedure was high and very few immediate or long-term complications were encountered.