This white paper describes gallbladder and biliary incidental findings found on CT and MRI. Recommendations for management are included. This represents the fourth of 4 such papers from the ACR Incidental Findings Committee II, which used a consensus method based on repeated reviews and revisions and a collective review and interpretation of relevant literature. Topics include the management of a variety of gallbladder abnormalities and biliary dilation. A table is provided for reference. © 2013 American College of Radiology.