We propose to develop and maintain a Data Coordinating Center (DCC) that will provide support for a network of clinical sites studying chronic pediatric liver disease. Specifically we will continue, expand, and merge the efforts of investigators from the Biliary Atresia Research Consortium (BARC) and the Cholestatic Liver Disease Consortium (CLiC) to form the Childhood Liver Disease Research Education Network (ChiLDREN). The specific aims of the ChiLDREN DCC are to: 1. Integrate the data from all of the BARC and CLiC studies. 2. Continue to coordinate and refine the ongoing studies in these networks, providing assistance as necessary and monitoring sites for data quality. 3. Provide expertise in the design, conduct, and analysis of studies to be performed by the network. 4. Develop plans for data analysis, perform the analysis, and collaborate in the preparation of the presentations and publications that will arise from these studies. 5. Maintain the database for specimen tracking to coordinate with the NIDDK repositories. 6. Develop effective administrative systems to provide timely consultation, review, and assistance with implementation for ancillary studies approved by the ChiLDREN Steering Committee. 7. Coordinate the efforts of the ChiLDREN Steering Committee and all ChiLDREN committees and working groups by providing leadership and logistic support. 8. Develop and modify the Data Safety and Monitoring Plan for ChiLDREN, and facilitate the work of the Data Safety Monitoring Board, by monitoring and reporting adverse events as well as providing regular progress reports. 9. Develop and maintain an effective ChiLDREN website that serves as a resource to patients and their families, as well as ChiLDREN investigators and coordinators. RELEVANCE (See instnjctions): Chronic pediatric liver disease is a devastating condition that has profound impact on children, their families, and our society. Biliary atresia, along with the other cholestatic liver diseases studied by the Network, account for over half of liver transplants performed in children in the United States. A better understanding of the diseases studied by this Network will help provide better care of patients with chronic liver disease.