To describe the process of initiating and organizing a nationwide validated web-based quality registry of gallstone surgery and endoscopic retrograde cholangiopancreatography (ERCP) and to present some clinical data and the impact the registry has had on the clinical treatment of gallstones. Observational, population-based registry study. Data from the nationwide Swedish Registry of Gallstone Surgery and ERCP (GallRiks). From May 1, 2005, to December 31, 2011, 63 685 cholecystectomies (laparoscopic and open) and 37 860 ERCPs have been prospectively registered in GallRiks. Cholecystectomies, laparoscopic or conventional, as well as ERCP in a population-based setting. Registrations of all cholecystectomies and ERCPs are performed online by the surgeon or endoscopist. Thirty-day follow-up of both gallstone surgery and ERCP is mandatory, as is an additional 6-month follow-up of the cholecystectomies. Scores on the 36-Item Short Form Health Survey are registered preoperatively and 6 months postoperatively in elective cholecystectomies at selected units. The 30-day overall complication rate is 6.1% in elective cholecystectomy, 11.2% in urgent cholecystectomy, and 12.0% following ERCP. The use of antibiotic and thromboembolic prophylaxis in elective laparoscopic cholecystectomy in Sweden has decreased by 8.7% and 17.8% (2006-2011), respectively, mainly owing to presentation of GallRiks data both at meetings and published in peer-reviewed publications. The large database has also enabled several research projects, including one demonstrating that the intention to perform intraoperative cholangiography reduced the risk of death after cholecystectomy. The database has reached greater than 90% national coverage and is continuously validated. GallRiks is a validated national quality registry for gallstone surgery and ERCP, serving as a base for audit of gallstone disease treatment. It also provides a database for clinical research.