This document summarizes the metabolism of bilirubin and provides an approach to evaluating a patient with hyperbilirubinemia. It discusses bilirubin production from breakdown of heme in red blood cells, its transport and conjugation in the liver, and excretion. It also reviews causes of unconjugated and conjugated hyperbilirubinemia, including increased production, decreased clearance, and defects in conjugation. The evaluation of a patient with jaundice involves obtaining a history and physical exam to help determine if the underlying etiology is liver disease, hemolytic disorder, or a metabolic defect.