Our understanding of the pathophysiology and of new treatments for inherited metabolic diseases that affect the liver continues to grow through the study of gene mutations and their functional effect on the proteins they encode. For genetic hemochromatosis and Wilson's disease, studies focused on the function of their respective gene products provide new insights into metal metabolism. For Crigler-Najjar syndrome, an inherited disorder that results in failure of proper bilirubin glucuronidation, the once futuristic idea of treatment by transplantation of donor hepatocytes has now proven successful in a human recipient. With continued study and experimentation, our diagnostic and therapeutic capabilities will continue to expand for these and other inherited metabolic disorders. Although this increase in new information has sparked numerous reviews of these subjects, the following are highlights from the past year that include information relative to disease diagnosis and treatment, as well as new insights into pathogenesis.