Background:Endoscopic Retrograde Cholangio Pancreatography (ERCP) is an established method in the treatment of complicated gallstone and other hepatobiliary diseases. This invasive method is, however, not without complications, mainly pancreatitis, bleeding and perforation. In this study we present data from, to our knowledge, the first web based national register of ERCP in the world. Methods:The Swedish Register for Gallstone Surgery and ERCP (GallRiks) started in May 2005. It comprises open and laparoscopic surgery of the gallbladder as well as all endoscopic interventions of the bile ducts. GallRiks is an internet application with on line registration of procedures and follow up as well as electronic reports on demand. Since the start an increasing number of Swedish hospitals have joined the register and the material now constitutes approximately 75% of all ERCPs in Sweden. During 2007 a total of 5040 ERCP examinations were registered. The 30 day follow up was incomplete in 43 patients and thus 4997 web-based ERCP registrations were available for evaluation. Results:Deep cannulation of the bile duct was achieved in 88%. The technique to cannulate with a guidewire seems to have been generally adopted in Sweden and was used in 84% of the examinations. In 2 % of the cases a complication was detected during the procedure and at 30 day follow-up the overall complication rate was 11%. Pancreatitis was found in 2.4%, bleeding in 0.80% and perforation in 0.28% of the examinations. The procedures were performed with the patient sedated with midazolam (47%), propophol (37%) or in general anaesthesia with intubation (16%).Cannulation of the bile duct was significantly less successful using sedation with midazolam (87.4%) compared to propophol (93.5%). Conclusion:“GallRiks” is a new national register for cholecystectomy and ERCP in Sweden with a current registration frequency of 75% of all ERCP performed in Sweden in 2007. This is the first publication of data from GallRiks. The complication rate of ERCP is in accordance with international standards and the technique of using a guide wire for cannulation is widespread in Sweden. An adequate sedation seems to improve the cannulation success rate.