Primary sclerosing cholangitis (PSC) is a rare liver disease that damages the liver's bile ducts. Bile ducts are tiny tubes that carry bile from the liver to the small intestine. Bile is a liquid produced by the liver that helps us absorb and use the nutrients in the food we eat. In people with PSC, the bile backs up into the liver and will damage it, causing scarring of the liver. The purposes of this study are to: - Collect medical and other data to learn more about PSC, how it progresses, and identify factors that may cause the disease to progress more quickly. - Ask questions about how PSC symptoms affect your child's life to learn more about its impact on your child's daily functioning - Children with PSC who are seen at one of the participating clinical sites in the Childhood Liver Disease Research Network (ChiLDReN) will be asked to contribute information, DNA, and other specimens. The information and specimens will be available to investigators to carry out approved research aimed at learning more about the possible causes and long-term effects of PSC.